CN111757488A

CN111757488A - Method and device for sending and receiving random access signal

Info

Publication number: CN111757488A
Application number: CN201910253163.3A
Authority: CN
Inventors: 苗婷; 毕峰; 卢有雄; 刘文豪; 邢卫民; 张峻峰
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2019-03-29
Filing date: 2019-03-29
Publication date: 2020-10-09
Also published as: WO2020199734A1

Abstract

The invention provides a method and a device for sending and receiving a random access signal, wherein the receiving method comprises the following steps: a first node sends resource configuration information to a second node; the first node receives a random access signal sent by the second node according to the resource configuration information, wherein the resource configuration information is used for indicating the second node to send the random access signal at an effective random access opportunity. The invention solves the problem of judging the effectiveness of the random access time in the related technology, thereby achieving the effects of judging the effectiveness of the random access time more reasonably, reducing the sending of useless signals and avoiding unnecessary interference and power consumption.

Description

Method and device for sending and receiving random access signal

Technical Field

The present invention relates to the field of communications, and in particular, to a method and an apparatus for transmitting and receiving a random access signal.

Background

A New generation mobile communication system (New Radio, abbreviated as NR) allows a more flexible network networking approach and the existence of New types of network nodes than 2G, 3G, 4G systems. Currently, a new type of Node Integrated Access and Backhaul Node (Integrated Access and Backhaul Node, abbreviated as IAB) that integrates a Backhaul Link (Backhaul Link) and a normal NR Access Link (Access Link) can provide a coverage and networking mode that is more flexible than a single cellular coverage, and will be an important component in a future mobile communication network.

For a new generation mobile communication system using an IAB node, the IAB node may be regarded as a normal terminal UE, or may be regarded as a base station to which other UEs access, because in a half-duplex operation mode, the IAB node cannot simultaneously transmit and receive, and a deployment location, an antenna configuration, and mobility of the IAB node are greatly different from those of the normal UE, these have certain limitations and requirements on configuration of random access resources, and in addition, redundant connection of the IAB node and resource configuration of an IAB node DU may also affect configuration of the random access resources. Therefore, how to judge the effectiveness of the random access opportunity and reduce the sending of useless signals so as to avoid unnecessary interference and power consumption is a problem to be solved.

In view of the above technical problems, no effective solution has been proposed in the related art.

Disclosure of Invention

The embodiment of the invention provides a method and a device for sending and receiving a random access signal, which are used for at least solving the problem of effectiveness judgment of random access time in the related technology.

According to an embodiment of the present invention, there is provided a method for receiving a random access signal, including: a first node sends resource configuration information to a second node; the first node receives a random access signal sent by the second node according to the resource configuration information, wherein the resource configuration information is used for indicating the second node to send the random access signal at an effective random access opportunity.

According to another embodiment of the present invention, there is provided a method for transmitting a random access signal, including: the second node receives the resource configuration information sent by the first node; the second node determines the effectiveness of the random access opportunity based on the resource configuration information; and the second node sends a random access signal to the first node at the effective random access opportunity.

According to another embodiment of the present invention, there is provided a receiving apparatus of a random access signal, including: a first sending module, configured to send resource configuration information to a second node; the first receiving module is configured to receive a random access signal sent by a second node according to resource configuration information, where the resource configuration information is used to instruct the second node to send the random access signal at an effective random access time.

According to another embodiment of the present invention, there is provided a transmission apparatus of a random access signal, including: a second receiving module, configured to receive resource configuration information sent by the first node; a determining module, configured to determine validity of a random access occasion based on the resource configuration information; and the second sending module is used for sending the random access signal to the first node at the effective random access time.

According to a further embodiment of the present invention, there is also provided a storage medium having a computer program stored therein, wherein the computer program is arranged to perform the steps of any of the above method embodiments when executed.

According to yet another embodiment of the present invention, there is also provided an electronic device, including a memory in which a computer program is stored and a processor configured to execute the computer program to perform the steps in any of the above method embodiments.

According to the invention, as the first node sends the resource configuration information to the second node, the first node receives the random access signal sent by the second node according to the resource configuration information, the purpose that the first node and the second node judge the effectiveness of the random access time based on the resource configuration information is realized, the second node sends the random access signal in the effective random access time, and the first node receives the random access signal in the effective random access time. Therefore, the problem of effectiveness judgment of the random access time existing in the related technology can be solved, the effectiveness of the random access time can be judged more reasonably, and the effect of reducing useless signal transmission so as to avoid unnecessary interference and power consumption is achieved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

fig. 1 is a block diagram of a hardware structure of a mobile terminal of a method for receiving a random access signal according to an embodiment of the present invention;

fig. 2 is a flowchart of a method of receiving a random access signal according to an embodiment of the present invention;

FIG. 3 is an architectural diagram of an IAB network;

FIG. 4 is a diagram illustrating a structure of a MAC PDU according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of reserved bits included in a MAC PDU in accordance with an alternative embodiment of the present invention;

fig. 6 is a flowchart of a method of transmitting a random access signal according to an embodiment of the present invention;

fig. 7 is a block diagram of a structure of a receiving apparatus of a random access signal according to an embodiment of the present invention;

fig. 8 is a block diagram of a structure of a transmission apparatus of a random access signal according to an embodiment of the present invention.

Detailed Description

The invention will be described in detail hereinafter with reference to the accompanying drawings in conjunction with embodiments. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order.

The method provided by the embodiment of the application can be executed in a mobile terminal, a computer terminal or a similar operation device. Taking the operation on a mobile terminal as an example, fig. 1 is a hardware structure block diagram of the mobile terminal of a method for receiving a random access signal according to an embodiment of the present invention. As shown in fig. 1, the mobile terminal 10 may include one or more (only one shown in fig. 1) processors 102 (the processor 102 may include, but is not limited to, a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 104 for storing data, and optionally may also include a transmission device 106 for communication functions and an input-output device 108. It will be understood by those skilled in the art that the structure shown in fig. 1 is only an illustration, and does not limit the structure of the mobile terminal. For example, the mobile terminal 10 may also include more or fewer components than shown in FIG. 1, or have a different configuration than shown in FIG. 1.

The memory 104 may be used to store a computer program, for example, a software program of application software and a module, such as a computer program corresponding to the method for receiving the random access signal in the embodiment of the present invention, and the processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, so as to implement the method described above. The memory 104 may include high speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 104 may further include memory located remotely from the processor 102, which may be connected to the mobile terminal 10 via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.

The transmission device 106 is used for receiving or transmitting data via a network. Specific examples of the network described above may include a wireless network provided by a communication provider of the mobile terminal 10. In one example, the transmission device 106 includes a Network adapter (NIC), which can be connected to other Network devices through a base station so as to communicate with the internet. In one example, the transmission device 106 may be a Radio Frequency (RF) module, which is used for communicating with the internet in a wireless manner.

In this embodiment, a method for receiving a random access signal is provided, and fig. 2 is a flowchart of a method for receiving a random access signal according to an embodiment of the present invention, as shown in fig. 2, the flowchart includes the following steps:

step S202, a first node sends resource configuration information to a second node;

step S204, the first node receives a random access signal sent by the second node according to the resource configuration information, wherein the resource configuration information is used for indicating the second node to send the random access signal at an effective random access time.

Through the steps, the first node sends the resource configuration information to the second node, and receives the random access signal sent by the second node according to the resource configuration information, so that the purpose that the first node and the second node judge the effectiveness of the random access time based on the resource configuration information is achieved, the second node sends the random access signal in the effective random access time, and the first node receives the random access signal in the effective random access time. Therefore, the problem of effectiveness judgment of the random access time existing in the related technology can be solved, the effectiveness of the random access time can be judged more reasonably, and the effect of reducing useless signal transmission so as to avoid unnecessary interference and power consumption is achieved.

Alternatively, the execution subject of the above steps may be the first node (e.g. parent node parentbia node, donor IAB, IAB node DU, base station in IAB node), and the like, but is not limited thereto.

The first node in this embodiment may be a Donor IAB DU, or a parent IAB node DU, or a base station, and the second node may be an IAB node, or an IAB node MT, or a relay station, or a terminal.

In this embodiment, an IAB node may be considered as a terminal (UE), or may be considered as another UE or a base station accessed by the IAB node, fig. 3 is a schematic diagram of an architecture of an IAB network, and as shown in fig. 3, a node having a wired connection with a core network is called a donor IAB (donor IAB), and one donor IAB is wirelessly connected to one or more IAB nodes (IAB nodes) and provides a radio access function for UEs. There is no direct link between the IAB node and the core network, and its interaction with the core network requires one or more forwarding, and is finally realized by means of the donor IAB. The IAB node has two functions: 1) a Distributed Unit (DU) function, that is, an IAB node provides a radio access function for the UE or a sub-IAB node like a base station; 2) Mobile-Termination (MT) functionality, i.e. the IAB nodes, are controlled and scheduled by the node IAB or an upper IAB node (i.e. parent IAB node) like the UE.

The Link between the Donor IAB and the IAB nodes and the Link between the IAB nodes are generally called Backhaul Link (BL), and the Link between the IAB node and the UE is called Access Link (AL). Considering that the IAB network supports multi-hop (for example, for the subordinate node of IAB node3, the connection to the donor IAB can be made through 4 hops, and the interaction with the core network is completed through the donor IAB), for more clear description of the link, specifically, for a specific IAB node, the link between the IAB node and its parent node, i.e., parent IAB node (which may be a normal IAB node or a donor IAB), is referred to as parent backhaul link (parent BL), the link between the IAB node and its child node (child IAB node) is referred to as child backhaul link (child BL), and the link between the IAB node and the normal UE is referred to as child access link (child AL). In order to ensure the robustness of the parent backhaul link, the IAB network supports redundant connections, for example, one IAB node may have one or more potential parent nodes in addition to the current parent node, as shown in fig. 3, and there is a wireless connection between the IAB node4 and the doror IAB node, and also a potential wireless connection with the IAB node 1.

In this embodiment, it can be applied to transmission of a random access signal between IAB nodes. In the half-duplex operation mode, the IAB nodes cannot simultaneously transmit and receive, for example, when the IAB node 2MT transmits a Random Access Preamble to the IAB node1, the IAB node cannot simultaneously receive the Random Access Preamble transmitted by the child IAB node3 or the child UEs, and the deployment location, antenna configuration, and mobility of the IAB node are greatly different from those of the general UE.

Further, in NR Release15, the frequency domain configuration of random access resources is achieved by providing a random access occasion (PRACH opportunity, abbreviated as RO) of a start frequency and frequency domain multiplexing. The time domain configuration of the random access resource is given in the form of a table, different frequency range and duplex mode correspond to different tables, each table comprises 256 configurations, and the configuration index is 0 to 255. In actual configuration, the base station provides a configuration index. For example, in a TDD system with a frequency band above 6GHz (i.e., FR2and unpaired spectrum), the random access time domain resource configuration is shown in table 1 (only a part of the configuration is shown here due to the large number of rows in the table).

Table 1:

wherein the columns of table 1 have the following meanings:

column 1 PRACH config.index: a PRACH configuration index;

column 2 Preamble format: a random access format;

column 3 (containing x and y): x is a PRACH configuration period, the value is 1 to 16, and a unit radio frame, namely the PRACH configuration period is 10x milliseconds; y is a remainder modulo x from a System Frame Number (SFN), and has a physical meaning that a PRACH slot or a PRACH opportunity occurs in a few radio frames in a PRACH configuration period, for example, y is 0, which is the first radio Frame, and y is 0, which is the second radio Frame.

Column 4 Slot number: a time slot containing ROs. For the sub-6 GHz band (i.e., FR1), it is subframe number.

Column 5 Starting symbol: and the initial symbol number (0-13) of the RO in the PRACH time slot.

Column 6 Number of PRACH slots with a 60kHz slot: when the subcarrier spacing of the PRACH is 120kHz, the PRACH slot is the second slot within the 60kHz slot (parameter 1), or both slots within the 60kHz slot are PRACH slots (parameter 2).

Column 7 Number (#) of time-domain PRACH instances with a PRACH slot: the number of time domains RO within a PRACH time slot.

The 8 th column PRACH duration refers to the number of OFDM symbols occupied by each random access format. For example, a1, is 2 symbols; c2 is 6 symbols, C2 is 4 symbols, and the others are CP and GP. There is no practical physical significance to uniformly take the value of 0 for the random access long format (sequence length is 839).

In an optional embodiment, considering that the IAB node needs to satisfy a half-duplex constraint (half-duplex constraint), that is, cannot simultaneously transmit and receive, the resource configuration information of the IAB node may include at least one of the following: the configuration index of a Physical Random Access Channel (PRACH), the frequency domain resource of the PRACH, the mapping relation between a Synchronization Signal Block (SSB) and random access occasions (ROs) (RACH occasions), the initial logical root sequence index and cyclic shift (Ncs), the configuration period scaling factor (S) of the PRACH, the offset y _ offset based on a radio frame, the offset sf _ offset based on a subframe, the offset S _ offset based on a time slot, a time slot number, a subframe number, unavailable resource configuration and available resource configuration.

In this embodiment, the resource configuration information needs to satisfy the following condition: for an IAB node, the PRACH resources configured on its parentbackhaul link and child link (including the child access link and the child backhaul link) should be Time Division Multiplexed (TDM), i.e. orthogonal in the time domain. That is, the PRACH resource of the preamble transmitted by the IAB node MT is orthogonal in the time domain to the PRACH resource of the preamble received by the IAB node DU (i.e., the child UEs, the PRACH resource of the preamble transmitted by the child IAB nodes).

The coverage characteristics and mobility of the IAB node and the normal UE are different. The IAB Node is used as a special integration body of a base station and a terminal, the deployment position of the IAB Node is greatly different from that of a common terminal, for example, the IAB Node is usually fixed at the position such as under an eave, the hanging height of the IAB Node is much higher than that of the common terminal, and a direct path is conveniently established with a donor IAB Node; for example, the IAB Node often has more antennas than a common terminal; for example, the IAB Node may need to be located farther away from the IAB Node or the parent IAB Node than the normal terminal (e.g., the IAB Node4 in fig. 3), which exceeds the coverage of the normal terminal. In addition, the IAB nodes are usually fixed in position, that is, the channel condition is relatively stable, so the IAB nodes can configure a larger PRACH configuration period, that is, x in column 3 of the PRACH configuration table may be larger.

While different random access formats support different coverage, mobility, resistance to penetration loss, etc. Therefore, the ordinary UEs and the IAB nodes have different requirements on PRACH resources, and one IAB node or dornor IAB needs to configure different PRACH resources for the child UEs and the child IAB nodes, including configuring PRACH configuration indexes for the IAB nodes separately, PRACH frequency domain resources, mapping relationship between SSB and valid random access occasions ROs, and a preamble (including parameters for generating a preamble sequence such as a starting logical root sequence index and cyclic shift Ncs).

To reduce complexity, the PRACH time domain resource configuration of the IAB nodes may be simply extended based on the PRACH configuration table of the terminal UEs in NR Release15, including:

the PRACH configuration period x in the extended PRACH configuration table is assumed to be S, and the PRACH configuration period after extension is S x.

The offset y _ offset of the radio frame containing ROs in the PRACH configuration table, and/or the offset sb _ offset of the subframe containing ROs in the PRACH configuration table, and the offset s _ offset of the slot containing ROs.

The expanded PRACH configuration period is used as the PRACH configuration period of the IAB nodes, and the deviated radio frame or subframe or time slot is used as the subframe or time slot of the IAB nodes, wherein the subframe or the time slot contains the ROs; or the expanded PRACH configuration period is used as the PRACH configuration period of the IABnodes, and the Parent IAB node can directly configure the slot number to replace the slot number indicated by the PRACH configuration index. The slot number after replacement is a set of slot numbers containing the ROs; or the extended PRACH configuration period is used as the PRACH configuration period of the IAB nodes, and the Parent IAB node may directly configure a subframe number for replacing the subframe number indicated by the PRACH configuration index. The replaced subframe number is the set of subframe numbers that contain the ROs.

The slot number or subframe number is configured in any one of the following manners:

mode 1: and predefining multiple groups of configurations, wherein each group of configurations corresponds to a time slot index set or a subframe index set, each group of configurations is provided with an index, and the configuration index is provided for the IAB node MT.

Mode 2: indicated by bitmap. For example, the slot number or subframe number corresponding to the bit value 1 is used to replace the slot number or subframe number indicated by the PRACH configuration index.

For FR1, the length of bitmap is the number of subframes contained in a radio frame, and for FR2, the length of bitmap is the number of time slots of a 60kHz subcarrier interval contained in a radio frame; alternatively, for all frequency bands, the bitmap length is the number of time slots of the 60kHz subcarrier spacing contained in the radio frame, and for FR1, only a part of bits are valid, for example, 10 bits lower or 10 bits higher.

If the PRACH resource configurations of UEs and IAB nodes are different, the IAB nodes may determine whether the cell can provide service for the IAB nodes according to the PRACH resource configuration of the cell during initial access or handover. To avoid selecting cells that cannot serve the IAB nodes.

Since PRACH resources configurations of UEs and IAB nodes are different, UEs may not know PRACH resources of IAB nodes, and therefore, if Random Access Responses (RARs) of UEs and IAB nodes are multiplexed, a case may occur where only one of UEs and IAB nodes can successfully perform Random Access even though PRACH resources used by UEs and IAB nodes are different. For example, the UE and the IAB node MT use the same PRACH time-frequency resources, but the random access format and the preamble sequence are different (but the sequence indices both range from 0 to 64). That is, the IAB node generates the initial root sequence index of the preamble sequence, and the cyclic shift is different from that of the normal terminal, and it is expected that the normal terminal and the IAB terminal (IAB node MT) can be successfully accessed at the same time even if the same PRACH time-frequency resource and preamble sequence identifier are used. However, the existing mechanism enables the UE and the IAB node to correspond to the same RAR, and at most, only one random access can be successful. For another example, the PRACH resources of the UE and the IAB node have the same time domain starting position, but are orthogonal in the frequency domain (i.e. FDM), since the resource indexes of the UE and the IAB node in the frequency domain are both started from 0, for example, 8 common terminals are multiplexed in the frequency domain, 4 IAB nodes are multiplexed, and the frequency domain resource indexes corresponding to the two are 0 to 7 and 0 to 4, respectively. Therefore, even though the RACH resources of the two terminals do not overlap, the calculated RA-RNTIs may be the same, and if the preamble sequence identifiers used by the two terminals are also the same, the two terminals will correspond to the same RAR, and at most one random access can be successful. This not only increases the random access delay of the normal terminal or the IAB terminal, but also causes unnecessary interference in the subsequent random access procedure. Therefore, RARs that distinguish UEs from IAB nodes are needed. For example, the IAB nodes use RA-RNTI calculation formulas different from UEs, or indicate MAC RAR of the IAB terminal (IAB node MT) by using reserved field of MAC (Medium Access Control) RAR (Random Access Response).

The RA-RNTI is used to scramble a Cyclic Redundancy Check (CRC) of the PDCCH corresponding to the random access response.

In an optional embodiment, the frequency domain resources of the PRACH include: a starting frequency of resources of the PRACH; the number of PRACH multiplexed in the frequency domain. In this embodiment, the starting frequency of the resources of the PRACH may be determined by one of the following ways: the first node determines the starting frequency of the resources of the PRACH based on the activated upstream bandwidth BWP; the method comprises the steps that a first node determines the starting frequency of PRACH resources based on the offset of a starting physical resource block PRB of the PRACH frequency domain resources initially accessed by terminal equipment; the method comprises the steps that a first node determines the starting frequency of resources of the PRACH based on the offset of a termination PRB of the initial access PRACH frequency domain resources of terminal equipment;

in this embodiment, the start frequency may be defined based on an activated uplink Bandwidth part (BWP) or may be defined based on an offset of a start PRB or a stop PRB of a PRACH frequency domain resource initially accessed by UEs. For example, the starting frequency is an offset from the first Physical Resource Block (PRB) of the active uplink BWP, i.e., an offset from PRB 0. Alternatively, the starting frequency is the offset of the first PRB or the offset of the last PRB with respect to the PRACH frequency domain resource to which UEs initially access.

Optionally, the PRB corresponds to a subcarrier interval corresponding to an activated uplink BWP.

Optionally, the default value for the starting frequency is PRB0 for the active upstream BWP.

Optionally, the activated upstream BWP is an initially activated upstream BWP in the initial access stage or an activated upstream BWP after the initial access.

Where the starting logical root sequence index and cyclic shift Ncs are used to generate the IAB nodes specific preamble.

Optionally, a part of the 64 preambles for UEs random access may also be designated as dedicated preambles for IABnodes.

The number of IAB nodes is less than UEs, so the total number of preambles dedicated for IAB nodes may be less than 64, such as 8, 16, 32.

In an alternative embodiment, the offset y _ offset of the radio frame comprises: and the offset is relative to a preset parameter y in a preset resource configuration table of the PRACH, wherein the preset parameter y refers to a radio frame index containing PRACH opportunity in a PRACH configuration period, and the preset parameter y is used for indicating a radio frame containing the PRACH opportunity in the PRACH configuration period.

Where y _ offset may be an offset from the parameter y in the PRACH configuration table, or an amount to replace the parameter y.

The IAB PRACH configuration period is assumed to be a maximum of Tmax frames. SFN including ROs satisfies:

mod (SFN, x S) ═ mod (y + y _ offset, x S), where 0 ≦ y _ offset < Tmax or 0 ≦ y _ offset < x S. Alternatively, the first and second electrodes may be,

mod (SFN, min { x S, Tmax }) -, mod (y + y _ offset, min { x S, Tmax }), where 0 is no more than y _ offset < Tmax or 0 is no more than y _ offset < x S or 0 is no more than y _ offset < min { x S, Tmax }.

The subframe-based offset sf _ offset is an offset from a subframe number in the PRACH configuration table.

The slot-based offset s _ offset is an offset from the slot number in the PRACH configuration table.

According to existing protocols, the slot/subframe number is the number within one radio frame (10ms), 1ms per subframe, with the slot number relative to the 60kHz subcarrier spacing. Since a radio frame contains 10 subframes, the subframe number after the offset sf _ offset and the value range of sf _ offset are as follows:

SF _ number mod (SF _ number + SF _ offset,10), where 0 ≦ SF _ offset < 10;

wherein, SF _ number represents the subframe number corresponding to the Rel-15PRACH configuration index, and SF _ number represents the subframe number after the SF _ offset is offset.

Since one radio frame contains 40 slots of 60kHz, the number of slots after the offset s _ offset and the range of s _ offset are as follows:

s _ number mod (S _ number + S _ offset,40), where 0 ≦ S _ offset < 40;

wherein, S _ number represents slot number corresponding to Rel-15PRACH configuration index, and S _ number represents subframe number after offset S _ offset.

Wherein, for each PRACH configuration index, a PRACH configuration period scaling factor S is configured separately; alternatively, one PRACH configuration period scaling factor is configured for the entire PRACH configuration table.

If the IAB nodes (IAB terminal) are not configured with the following parameters: any one or any combination of the PRACH configuration index, the PRACH frequency domain resource, the mapping relationship between the SSB and the valid ROs, or any other parameter related to the PRACH resource that is not configured for the IAB nodes, then the IAB nodes reuse the corresponding parameter in the PRACH resource configuration of the UEs.

The IAB nodes determine the PRACH resource according to the PRACH configuration index and the PRACH frequency domain resource by combining at least one of a scaling factor S, an offset y _ offset, an offset S _ offset and an offset sf _ offset.

Alternatively, for the scaling factor S, the offset y _ offset, the offset S _ offset, and the offset sf _ offset, if not configured, the default value is 0.

In an alternative embodiment, in addition to the above parameters, the parent IAB node needs to provide the IAB nodes with at least one PRACH related parameter as follows: the method comprises the steps of obtaining the total number of available random access lead codes, the total number of contention-based lead codes corresponding to each SSB, the total number of contention-based lead codes in a group A corresponding to each SSB, a threshold of the size of a transmission block of a selected preamble group, a path loss calculation parameter of the selected preamble group, a subcarrier interval used by a random access signal (msg1), an SSB received power threshold which needs to be met by the selected SSB and a corresponding PRACH resource, a power related parameter, a constraint set configuration, precoding of msg3 and the like.

In an alternative embodiment, the subframe number comprises: and the subframe number indicated by the PRACH configuration index in the preset resource configuration table for replacing the PRACH, wherein the replaced subframe number is an index set comprising the ROs subframes. The slot number includes: and the time slot number is used for replacing the time slot number indicated by the PRACH configuration index in the preset resource configuration table of the PRACH, wherein the replaced time slot number is an index set comprising the ROs time slot.

In the above embodiment, it is assumed that the PRACH configuration period of the IAB nodes is a maximum of Tmax system frames. Alternatively, Tmax is one of 16,32,64,128, 256. Scaling factor S2^kWhere k is a non-negative integer, i.e. S is a power of 2, the maximum of which depends on the maximum of the PRACH configuration period of the IAB nodes.

For each PRACH configuration index, the maximum value of S depends on the maximum value Tmax of the PRACH configuration period of the IAB nodes and the value of x in the PRACH configuration index, e.g., the maximum value of S is Tmax divided by x.

For the IAB nodes, the system frame number SFN containing the ROs can be determined according to several ways:

mode 1: SFN satisfies mod (SFN, S x) ═ mod (y + y _ offset, S x), where y _ offset is an integer, and 0 is not less than y _ offset < Tmax or 0 is not less than y _ offset < S x or 0 is not less than y _ offset < min { x S, Tmax }.

Mode 2: y _ offset, that is, the parameter y in the configuration table is directly replaced, that is, the SFN satisfies mod (SFN, x _ S) — y _ offset, where y _ offset is an integer and 0 ≦ y _ offset < S ×.

3) If y in the PRACH configuration index includes multiple values, y _ offset is the first value y1 of the parameter y, and the other values in the parameter y are the difference + y _ offset between the corresponding value and y1 in the PRACH configuration table, for example, y ═ y1, y2 in the PRACH configuration table, then y ═ y _ offset, y _ offset + y2-y1 from y _ offset, otherwise y ═ y _ offset. Wherein y _ offset is an integer, and y _ offset < S x is greater than or equal to 0;

wherein y is a parameter y in the PRACH configuration table.

It should be noted that if S × x > Tmax, S × x is Tmax, otherwise, the above formula is not changed.

Considering that in NR R15, for FR1, each PRACH configuration index corresponds to a y value, i.e. all ROs within a PRACH configuration period are contained within a frame; for the FR2 frequency band, there is usually only one y value, and a few corresponding configurations are y {1,2}, considering that the channel conditions between IAB nodes are relatively stable, it is not necessary to configure multiple frames including ROs within one PRACH configuration period, so the method 2 is a simpler and more intuitive y _ offset scheme.

In an alternative embodiment, the RA-RNTI may be calculated with a different PRACH frequency domain index number or offset to the PRACH frequency domain index number.

In the existing protocol, the maximum number of PRACH multiplexed by the UE in the frequency domain is 8, and the range of the index number f _ id is an integer of which f _ id is greater than or equal to 0 and less than or equal to 8, so that the PRACH indexes multiplexed by the IAB node in the frequency domain can be numbered from 8, assuming that the maximum number of PRACH multiplexed by the IAB node in the frequency domain is Nprach, the value of Nprach can be predefined, and the value of RA-RNTI is smaller than 65519. The PRACH index number multiplexed by the IAB node on the frequency domain is an integer with f _ id being more than or equal to 8 and less than 8+ Nprach.

In order to distinguish from the RA-RNTI (Random Access RNTI, RNTI: Radio Network temporary identifier) of the UE, for the IAB nodes, the RA-RNTI corresponding to the PRACH transmitting the Random Access preamble is calculated by the following formula:

RA-RNTI ═ 1+ s _ id +14 × t _ id +14 × 80 × f _ id +14 × 80 × (8+ Nprach) × ul _ carrier _ id formula 1;

wherein s _ id is the first OFDM symbol index of a given PRACH (0 ≦ s _ id <14), t _ id is the first slot index of a given PRACH within a system frame (0 ≦ t _ id <80), f _ id is the PRACH index given in the frequency domain (8 ≦ f _ id <8+ Nprach), ul _ carrier _ id is used to indicate the uplink carrier for transmitting the random access preamble (0 represents normal uplink carrier, 1 represents supplemental uplink carrier)

In another embodiment, the PRACH index multiplexed on the frequency domain by the IAB node is numbered from 0, and f _ id is offset by 8 in the RA-RNTI calculation formula for the IAB nodes, so that for the IAB nodes, the RA-RNTI corresponding to the PRACH that transmits the random access preamble is calculated by the following formula:

RA-RNTI ═ 1+ s _ id +14 × t _ id +14 × 80 × (f _ id +8) +14 × 80 × (8+ Nprach) × ul _ carrier _ id formula 2;

wherein s _ id is the first OFDM symbol index of a given PRACH (0 ≦ s _ id <14), t _ id is the first slot index of the given PRACH within the system frame (0 ≦ t _ id <80), f _ id is the PRACH index given in the frequency domain (0 ≦ f _ id < Nprach), ul _ carrier _ id is the uplink carrier used to indicate transmission of the random access preamble (0 denotes normal uplink carrier, 1 denotes supplemental uplink carrier).

Alternatively, Nprach is 8, then the two

equations

1 and 2 are:

RA-RNTI＝1+s_id+14×t_id+14×80×f_id+14×80×16×ul_carrier_id。

RA-RNTI＝1+s_id+14×t_id+14×80×(f_id+8)+14×80×16×ul_carrier_id

in an alternative embodiment, the RA-RNTI may be calculated using a different slot index or offset to the slot index.

The slot indices for the IAB nodes in the radio frame are numbered from 80, i.e. the first slot index in the radio frame is 80, the second 81, and so on.

Therefore, for the IAB nodes, the RA-RNTI corresponding to the PRACH transmitting the random access preamble is calculated by the following formula:

RA-RNTI＝1+s_id+14×t_id+14×160×f_id+14×160×8×ul_carrier_id

wherein s _ id is the first OFDM symbol index of a given PRACH (0 ≦ s _ id <14), t _ id is the first slot index of the given PRACH within the system frame (80 ≦ t _ id <160), f _ id is the PRACH index given in the frequency domain (0 ≦ f _ id <8), ul _ carrier _ id is an uplink carrier used to indicate transmission of the random access preamble (0 denotes normal uplink carrier, 1 denotes supplementary uplink carrier).

In another embodiment, the slot index of the IAB nodes in the radio frame is numbered from 0, and t _ id in the RA-RNTI calculation formula for the IAB nodes is offset by 80.

RA-RNTI＝1+s_id+14×(t_id+80)+14×160×f_id+14×160×8×ul_carrier_id

wherein s _ id is the first OFDM symbol index of a given PRACH (0 ≦ s _ id <14), t _ id is the first slot index of the given PRACH within the system frame (0 ≦ t _ id <80), f _ id is the PRACH index given in the frequency domain (0 ≦ f _ id <8), ul _ carrier _ id is an uplink carrier used to indicate transmission of the random access preamble (0 denotes a normal uplink carrier, 1 denotes a supplemental uplink carrier).

In an optional embodiment, the RA-RNTI corresponding to the PRACH transmitting the random access preamble may also be calculated by the following formula:

RA-RNTI＝1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id+14×80×8×2×identifier

wherein s _ id is the first OFDM symbol index of a given PRACH (0 ≦ s _ id <14), t _ id is the first slot index of the given PRACH within a system frame (0 ≦ t _ id <80), f _ id is the PRACH index given in the frequency domain (0 ≦ f _ id <8), ul _ carrier _ id is the uplink carrier used for indicating transmission of the random access preamble (0 represents the normal uplink carrier, 1 represents the supplementary uplink carrier), identifier is used for indicating whether the RA-RNTI calculation formula is for the normal terminal or the IAB node, identifier is 0 for the normal terminal, and identifier is 1 for the IAB node.

In an optional embodiment, for an IAB terminal (IAB node MT), an RA-RNTI corresponding to a PRACH transmitting a random access preamble is calculated by the following formula:

RA-RNTI＝1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id+14×80×8×2

For a common terminal, the RA-RNTI corresponding to the PRACH for transmitting the random access preamble is calculated by the following formula:

RA-RNTI＝1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id

In an optional embodiment, for the IAB node, an RA-RNTI corresponding to a PRACH transmitting a random access preamble is calculated by the following formula:

RA-RNTI is 1+ s _ id + s × t _ id + s × t × f _ id + s × t × f × ul _ carrier _ id + s × t × f × 2; alternatively, the first and second electrodes may be,

RA-RNTI＝1+s_id+s×t_id+s×t×f_id+s×t×f×ul_carrier_id；

wherein s _ id is the first OFDM symbol index of a given PRACH (s0 ≦ s _ id < s), t _ id is the first slot index of a given PRACH within a system frame (t0 ≦ t _ id < t), f _ id is the PRACH index given in the frequency domain (f0 ≦ f _ id < f), ul _ carrier _ id is an uplink carrier for indicating transmission of a random access preamble (0 denotes a normal uplink carrier, and 1 denotes a supplemental uplink carrier).

The OFDM symbols in the slot are numbered from s0, that is, the index of the first OFDM symbol in the slot is s0, the index of the second OFDM symbol in the slot is s0+1, and so on;

the slot indexes in the radio frame are numbered from t0, that is, the first slot index in the radio frame is t0, the second slot index is t1, and so on; the slot indexes in the radio frame are numbered from t0, i.e. the first slot index in the radio frame is t0, the second is t0+1, and so on;

the PRACH indexes in the frequency domain are numbered from f0, that is, from a low frequency, the PRACH index of the first PRACH resource in the frequency domain is f0, the second is f0+1, and so on.

Where the values of s0, t0, f0, s, t, f need to be predefined, e.g., s 0-0, t 0-0, f 0-0, s-14, t-80, f-8; or s 0-14, t 0-0, f 0-0, s-28, t-80, f-8; or s 0-0, t 0-80, f 0-0, s-14, t-160, f-8; or s 0-0, t 0-0, f 0-8, s-14, t-80, and f-16.

In an alternative embodiment, the IAB nodes specific MAC RAR is indicated using a reserved field in the MAC RAR.

In NR Rel-15, as shown in fig. 4, one MAC PDU contains one or more MAC sub-PDUs, each consisting of one of:

-BI only: MAC subheader with Backoff indication only;

-rapid Access Preamble identifier only: MAC subheader with RAPID only (i.e. acknowledgement of system information request);

RAPID and RAR: MAC subheader with RAPID and MAC RAR.

Wherein if the MAC PDU contains BI only, the BI only is located at the beginning of the MAC PDU. RAPID only and RAPID and RAR can be placed anywhere in the MAC PDU between BI only and the padding bit (padding).

As shown in fig. 5, a reserved bit R in a MAC RAR may be used to indicate whether the MAC RAR is a MAC RAR of IAB nodes. For example, R ═ 0 indicates a MAC RAR that is not an IAB nodes, and R ═ 1 indicates a MAC RAR that is an IAB nodes, or vice versa.

Each MAC RAR corresponds to a subheader (subheader) including RAPID, the subheader and the MAC RAR form a MAC sub-PDU, and if the RAPID corresponding to the random access signal sent by the normal terminal (UEs) in the MAC PDU is the same as the RAPID corresponding to the random access signal sent by the IABnodes, the MAC sub-PDU of the normal terminal should be in front of the MAC sub-PDU of the IABnodes. For example, the MAC sub pdu corresponding to the terminal is nth, the MAC sub pdu corresponding to the IAB nodes is nth + k, and k is a positive integer.

When the PRACH time-frequency resources of the normal terminal and the IAB terminal that send the preamble signal are the same, and the preamble index is the same, the RA-RNTI of the normal terminal and the IAB terminal are the same, and the RAPID of the normal terminal and the IAB terminal are also the same, so their MAC RARs are multiplexed in one MAC PDU, and in order for the IAB terminal to be able to distinguish its own MAC RAR, the reserved bit R in the MAC RAR may be used to indicate whether the MAC RAR is the MAC RAR of the IAB terminal. In order to avoid that the normal terminal erroneously detects the MAC RAR of the IAB terminal, the MAC sub PDU of the normal terminal should precede the MAC sub PDU of the IAB terminal in the MAC PDU.

Because the common terminal can not identify the R, the common terminal can be prevented from taking the MAC RAR of the IAB terminal as the common terminal, so that the access failure is avoided, and the initial access of the IAB terminal can be influenced.

It should be noted that, in the above calculation formula of all RA-RNTIs in the example, for

random access formats

0, 1,2, and 3 (i.e. long formats with preamble length 839), s _ id and t _ id are determined according to the subcarrier interval of the activated uplink BWP where the PRACH resource is located. For the random access formats a1/B1, a2/B2, A3/B3, a1, a2, A3, B1, B4, C0, and C2 (i.e., preamble length is 139 short format), s _ id and t _ id are determined according to the subcarrier interval of the activated uplink BWP where the PRACH resource is located, or determined according to the subcarrier interval of the PRACH, and a protocol is required to be predefined.

Optionally, for the random access formats a1/B1, a2/B2, A3/B3, a1, a2, A3, B1, B4, C0, C2 (i.e. preamble length 139 short format), s _ id and t _ id are determined according to the subcarrier spacing of PRACH.

In an alternative embodiment, the validity of the random access occasion may be determined by one of the following methods:

in the case where the first node does not provide uplink and downlink configuration for time division duplexing to the second node, the random access occasion is valid if the random access occasion satisfies the following condition: the random access opportunity is not in front of the SSB in the time slot of the PRACH, the starting point of the random access opportunity is after at least Ngap symbols of the last SSB receiving symbols, and the random access opportunity is not overlapped with the specific resource in the time domain;

under the condition that the first node provides uplink and downlink configuration of time division duplex for the second node, the random access time is effective under the condition that the random access time meets one of the following conditions: the random access opportunity is in the uplink symbol, and the random access opportunity is not overlapped with the specific resource in the time domain; the random access opportunity is not in front of SSB in the PRACH time slot, the starting point of the random access is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is not overlapped with specific resources on the time domain; the random access opportunity is not in front of the SSB in the PRACH time slot, the starting point of the random access is behind at least Ngap symbols of the last SSB receiving symbols, and the random access opportunity is not overlapped with the specific resource in the time domain; the random access opportunity is not in front of the SSB in the PRACH time slot, the starting point of the random access is behind at least Ngap symbols of the last SSB receiving symbols, the starting point of the random access is behind at least Ngap symbols of the last downlink symbols, and the random access opportunity is not overlapped with the specific resource in the time domain;

wherein the specific resource comprises at least one of: the resource indicated by the unavailable resource configuration, the resource which can not be used by the second node, the hard resource of the base station unit of the second node, the hard resource which is used for transmitting the important signal or channel by the base station unit of the second node, the hard UL resource of the base station unit of the second node, and the hard UL resource which is used for transmitting the important signal or channel by the base station unit of the second node;

the important signals or channels include at least one of: SSB, system information, PRACH, signal or channel of URLLC.

In this embodiment, the IAB node has two functional units MT and DU, where MT is a unit in the IAB node that serves as a UE function, and therefore, the resource type of MT includes downlink time resource (D), uplink time resource (U), and flexible time resource (F), which can be flexibly used as uplink or downlink resource, as in the case of a normal UE. For the DU, its resource types are: d, U, F, unavailable time resource (NA). Wherein, NA refers to the resource that DU can not use, and each of D, U and F has the following two types of attributes: hard (hard), which refers to the resources that are always available to the DU, and soft (soft), whether soft resources are available may be further indicated by explicit or implicit means. The resources for the DU thus include the following 7 types: hardD, soft D, hard U, soft L, hard F, soft F, NA.

The IAB node DU resource configuration needs to consider the trade-off between configuration flexibility and bit overhead, and since the IAB node DU is to provide services for a general UE, the resource configuration of the DU may also be limited by the common TDD uplink and downlink configuration (e.g. TDD-UL-DL-configuration common) mode of Release15, and therefore, for one IAB node, since the PRACH time domain resource configuration is selected from the table and the selection is also affected by the common TDD uplink and downlink configuration, the NA resource of the parentianiab node DU may overlap in the time domain with the PRACH resource configured by the parent IAB node for the IAB node MT. In addition, for one IAB node, it is very likely that the hard resource of the IAB node DU and the PRACH resource configured by the parent IAB node for the IAB node MT overlap in the time domain. In this case, a related scheme is needed to enable the IAB node to operate under half-duplex constraints.

In addition, the IAB node may need to be randomly accessed to other iabb nodes except the current parent IAB node, and for convenience of description, we refer to the IAB node as a potential parent IAB node. IAB node4 as in fig. 3 may need random access to IAB node1 in addition to random access to the donor IAB (i.e. parent IAB node), e.g. maintaining substantial synchronization with IAB node1 to enable fast handover to IAB node1 when the link quality between IAB ndoe4 and donor IAB is poor, or IAB node4 may need to perform random access to IAB node1 and handover to IAB node 1. Namely, IAB node1 is a potential parent IAB node of IAB node 4. However, PRACH resources configured by the parent IAB node and the potential parent IABnode for the IAB node MT may be different, and therefore, even though the PRACH resource configured by the parent IAB node for the IAB node MT and the hard resource of the IAB node DU are not overlapped in the time domain, it is difficult to simultaneously ensure that the PRACH resource configured by one or more potential parent IAB nodes for the IAB node MT and the hard resource of the IAB node DU are orthogonal in the time domain. In this case, a related scheme is also required to enable the IAB node to operate under half-duplex constraints.

The random access opportunity obtained according to the PRACH resource configuration may be invalid, for example, the random access opportunity overlaps with the downlink signal SSB in a time domain, and due to half duplex or interference limitation, the parent IAB node cannot receive the uplink random access signal when transmitting the SSB, and therefore, the terminals (UEs or IAB node MTs) do not need to transmit the uplink random access signal, and therefore, a criterion for determining the validity of the random access opportunity needs to be formulated. Otherwise, not only interference is generated, but also mapping understanding of the two sides for receiving and transmitting the random access signal to the SSB and the random access occasion is inconsistent, resulting in random access failure.

In an alternative embodiment, the rule for determining the validity of the random access occasion is as follows:

for paired spectrum (frequency division duplex), all random access slots are active.

For unpaired spectrum, if time division duplex uplink and downlink configurations are not provided for the terminal, the random access opportunity is valid if the random access opportunity in the PRACH slot is not ahead of the SSBs in the PRACH slot and the random access opportunity start point is after at least Ngap symbols of the last SSB received symbols.

If the time division duplex uplink and downlink configuration is provided for the terminal, if the random access opportunity is in the uplink symbol; or, the random access opportunity is not in front of the SSB in the PRACH time slot, and the starting point of the random access opportunity is behind at least Ngap symbols of the last downlink symbol; or, the random access occasion is not before the SSB within the PRACH slot, and the start of the random access occasion is after at least Ngap symbols of the last SSB received symbol; or, the random access opportunity is not before the SSB in the PRACH slot, and the random access opportunity start is after at least Ngap symbols of the last downlink symbol, and the random access opportunity start is after at least Ngap symbols of the last SSB received symbols, then the random access opportunity is valid.

According to the above mechanism, the obtained effective random access time may not be available to the IAB terminal, so that the existing random access validity judgment mechanism needs to be enhanced, or the availability of the effective random access time judged by the existing mechanism needs to be further judged.

The PRACH time slot refers to a time slot corresponding to the PRACH subcarrier interval and containing the PRACH opportunity.

In an alternative embodiment, parent IAB node provides an unavailable resource configuration for IAB nodes, which is used to indicate the time resource that IAB node MT cannot use, i.e. the time resource that IAB node MT cannot use. If the PRACH resource configured by parent IABnodes for the IAB node MT overlaps with the unavailable resource in the time domain, the random access occasion overlapping with the unavailable resource in the time domain is invalid, that is, the IAB node MT cannot use the random access occasion overlapping with the unavailable resource in the time domain.

The PRACH resource may be a common PRACH resource configured by a system message, or may be a dedicated PRACH resource configured by dedicated RRC signaling.

The unavailable resource is a continuous time resource, or a discrete time resource.

Optionally, the unavailable resource may include at least one of: the method comprises the steps of determining unavailable resources of Parent IAB node DU, subset of the unavailable resources of the Parent IAB node DU, the unavailable resources of potential Parent IAB node DU, subset of the unavailable resources of potential Parent IAB node DU, hard resources of child IAB node DU of the Parent IAB node, hard UL resources of the child IAB node DU of the Parent IAB node, unusable PRACH resources, and determining the unavailable resources according to the realization of the Parent IAB node DU.

Alternatively, the child IAB node DU and IAB node MT are located in the same IAB node.

Optionally, the unavailable resource is a continuous time resource or a discrete time resource within each radio frame.

Optionally, the manner of indicating the unavailable resource in each radio frame is any one of the following: 1. k1 th to k2 th subframes or slots; 2. the last M1 subframes or slots; 3. the last M2 even-numbered subframes or slots; 4. the last M3 odd-numbered subframes or slots; 5. indicated with a Resource Indicator Value (RIV); 6. the length of the bitmap is the number of subframes or time slots contained in the radio frame, and whether 0 or 1 in the bitmap indicates unavailable resources is predetermined; 7. and grouping resources in a radio frame, wherein the grouped resources are used for bitmap to indicate one or more groups as unavailable resources.

The RIV is determined according to the number N of subframes or slots contained in the radio frame, the starting subframe or slot Tstart of the unavailable resource, and the number L of consecutive subframes or slots:

if (L-1) < floor (N/2),

then RIV ═ N (L-1) + Tstart,

otherwise, RIV ═ N (N-L +1) + (N-1-Tstart)

Wherein k1, k2, M1, M2 and M3 are integers less than or equal to N.

Optionally, the unavailable resource is a periodic unavailable continuous time resource or a discrete time resource.

Optionally, the unavailable resource configuration comprises a period, bitmap or RIV. Wherein, bitmap is used for 0 or 1 to indicate that one or more subframes or time slots in the period are unavailable resources. The length of the bitmap is the number of subframes or the number of slots contained in the period. Wherein, whether 0 or 1 in the pre-agreed Bitmap indicates an unavailable resource, for example, 0 in the agreed Bitmap indicates an unavailable resource. RIV indicates that one or more consecutive subframes or slots starting from a starting subframe or slot are unavailable resources, RIV calculation methods, and intra-radio indication.

Optionally, the unavailable resource configuration comprises at least one of the following parameters: period, offset within period O, duration t. The granularity of the offset O and the duration t in the period is a subframe or a time slot of the PRACH.

Optionally, for the above periods, the starting position of the first period is aligned with the starting position of the radio frame 0.

For unpaired spectrum (time division duplex), the effectiveness of a random access occasion is also related to the time domain location of the SSB and the time division duplex uplink and downlink configuration.

For unpaired spectrum, if no time division duplex uplink and downlink configuration is provided for the IAB node MT, the random access opportunity is valid if the random access opportunity is not ahead of the SSB within the PRACH slot and the random access opportunity start is after at least Ngap symbols of the last SSB received symbol, and the random access opportunity does not overlap the first resource in the time domain.

If the time division duplex uplink and downlink configuration is provided for the IAB node MT, if the random access opportunity is in an uplink symbol, and the random access opportunity is not overlapped with the first resource in the time domain; or the random access opportunity is not in front of the SSB in the PRACH time slot and the starting point of the random access opportunity is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is not overlapped with the first resource in the time domain; or the random access opportunity is not in front of the SSB in the PRACH time slot, and the random access opportunity starts after at least Ngap symbols of the last SSB received symbols, and the random access opportunity is not overlapped with the first resource in the time domain; or, the random access occasion is not before the SSB in the PRACH slot, and the start point of the random access is after at least Ngap symbols of the last SSB received symbol, and the start point of the random access is after at least Ngap symbols of the last downlink symbol, and the random access occasion is not overlapped with the first resource in the time domain, then the random access occasion is valid.

And the first resource is the resource indicated by the unavailable resource configuration. The IAB node MT may be obtained from the configuration of unavailable resources provided by parent IABnode for IAB nodes.

In an alternative embodiment, parent IAB node provides an available resource configuration for IAB nodes to indicate the time resources that IAB node MT can use, i.e. the available resources for IAB node MT. If the random access opportunity configured for the IAB node MT by parent IAB nodes is within the available resources, the random access opportunity is valid, i.e. the IAB node MT can use the random access opportunity within the available resources.

The available resources are either continuous time resources or discrete time resources.

Optionally, the available resources are any one or any combination of the following: available resources of Parent IAB node DU, a subset of available resources of Parent IAB node DU, available resources of potential Parent IAB node DU, a subset of available resources of potential Parent IAB node DU, unavailable resources NA of Parent IAB node DU, soft D resources of Parent IAB node DU, soft U resources of Parent IAB node DU, hard D resources of Parent IAB node DU, hard F resources of Parent IAB node DU, soft F resources of Parent IAB node DU, usable PRACH resources, the determination of available resources depends on the implementation of Parent IAB node DU.

Optionally, the child IAB node DU and the IAB node MT are located in the same IAB node.

The indication mode of the available resource is similar to the indication mode of the unavailable resource, and is not described herein again.

For unpaired spectrum, if no time division duplex uplink and downlink configuration is provided for the IAB node MT, the random access opportunity is valid if it is not in front of an SSB within a PRACH slot and the random access opportunity start is at least Ngap symbols after the last SSB received a symbol and the random access opportunity is within the available resources.

If the time division duplex uplink and downlink configuration is provided for the IAB node MT, if the random access time is in the uplink symbol and the random access time is in the available resources; or the random access opportunity is not in front of the SSB in the PRACH time slot and the starting point of the random access opportunity is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is in the available resources; or, the random access occasion is not before the SSBs in the PRACH slot, and the starting point of the random access is after at least Ngap symbols of the last SSB received symbols, and the random access occasion is within the available resources; or, the random access occasion is not before the SSB in the PRACH slot, and the random access starts after at least Ngap symbols of the last SSB received symbol, and the random access starts after at least Ngap symbols of the last downlink symbol, and the random access occasion is within the available resources, then the random access occasion is valid.

And the available resource is the resource indicated by the available resource configuration.

In an optional embodiment, the validity of the random access occasion may also be determined by:

for an IAB node, the hard resource of an IAB node DU is a resource that can be used by the DU, i.e., a sub-link (including a sub-access link and a sub-backhaul link) of the IAB node. If the hard resource of the IAB node DU overlaps with the PRACH resource configured by the parent IAB node for the IAB node MT in the time domain, the IAB node MT and the DU may not use the overlapping resource at the same time due to half-duplex limitation, so a processing method is: if the hard resource of the IAB node DU overlaps with the PRACH resource configured by the parent IAB node for the IAB node MT in the time domain, the random access opportunity overlapping with the hard resource of the DU in the time domain is invalid, that is, the IAB node MT cannot transmit the preamble signal using the random access opportunity overlapping with the hard resource of the DU in the time domain.

However, for an IAB node supporting Frequency Division Multiplexing (FDM) and Space Division Multiplexing (SDM), an IAB node MT and an IAB node DU can transmit or receive simultaneously, so if the hard resource is hard DL or hard F, the IAB node MT and the IAB node DU can transmit simultaneously, so the IAB node MT can consider that a random access opportunity overlapping with the hard DL or hard F of the DU in the time domain is still valid, and therefore, for the IAB node supporting Frequency Division Multiplexing (FDM) and Space Division Multiplexing (SDM), the validity of the random access opportunity can also be judged as follows: if the hard UL of the IAB node DU overlaps with the PRACH resource configured by the parent IAB node for the IAB node MT in the time domain, the random access occasion that overlaps with the hard UL of the DU in the time domain is invalid.

Since the resource configuration of the IAB node DU is obtained only after the initial access of the IAB node MT is completed, the IAB node MT cannot obtain the resource configuration of the IAB node DU during the initial access. Therefore, the resource configuration of the IAB node DU may be used only for validity determination of dedicated PRACH resources, or may be used for validity determination of common PRACH resources after initial access of the IAB node MT.

For unpaired spectrum, if no time division duplex uplink and downlink configuration is provided for the IAB node MT, the random access opportunity is valid if the random access opportunity is not ahead of the SSB within the PRACH slot and the random access opportunity start is after at least Ngap symbols of the last SSB received symbol, and the random access opportunity does not overlap in the time domain with the second resource.

If the time division duplex uplink and downlink configuration is provided for the IAB node MT, if the random access opportunity is in an uplink symbol, and the random access opportunity is not overlapped with the second resource in the time domain; or the random access opportunity is not in front of the SSB in the PRACH time slot and the starting point of the random access opportunity is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is not overlapped with the second resource in the time domain; or the random access opportunity is not in front of the SSB in the PRACH time slot, and the random access opportunity starts after at least Ngap symbols of the last SSB received symbols, and the random access opportunity is not overlapped with the second resource in the time domain; or, the random access opportunity is not before the SSB in the PRACH slot, and the start point of the random access is after at least Ngap symbols of the last SSB received symbol, and the start point of the random access is after at least Ngap symbols of the last downlink symbol, and the random access opportunity does not overlap with the second resource in the time domain, then the random access opportunity is valid.

The second resource is a hard resource of the IAB node DU, or a hard resource of the IAB node DU for transmitting an important signal or channel, or a hard UL resource of the IAB node DU for transmitting an important signal or channel.

Wherein, the important signal or channel is any one or any combination of the following: SSB, system information, PRACH, URLLC related signals or channels.

The tdd uplink/downlink configuration may be a common tdd uplink/downlink configuration, or a common tdd uplink/downlink configuration and a dedicated tdd uplink/downlink configuration.

The parent IAB node DU and the IAB node MT know the resource configuration of the IAB node DU, so that the judgment results of the validity of the random access opportunity are consistent. The problem that the random access performance is influenced due to the fact that the judgment results are inconsistent can be solved.

In an optional embodiment, the validity of the random access occasion may also be determined based on the hard resource and the unavailable resource configuration of the DU:

the parent IAB node provides the IAB nodes with unavailable resource configuration and is used for indicating the time resources which cannot be used by the IAB node MT, namely the unavailable resources of the IAB node MT. If the PRACH resource configured by parent IAB nodes for the IAB node MT overlaps with the unavailable resource in the time domain, the random access occasion that overlaps with the unavailable resource in the time domain is invalid, that is, the IAB node MT cannot use the random access occasion that overlaps with the unavailable resource in the time domain.

In addition, the IAB node MT may further determine the validity of the random access occasion in combination with the resource configuration of the IAB node DU. That is to say that the first and second electrodes,

For unpaired spectrum, if no time division duplex uplink and downlink configuration is provided for the IAB node MT, the random access opportunity is valid if the random access opportunity is not ahead of the SSB within the PRACH slot and the random access opportunity start is after at least Ngap symbols of the last SSB received symbol, and the random access opportunity does not overlap in time domain with both the first and second resources.

If the time division duplex uplink and downlink configuration is provided for the IAB node MT, if the random access opportunity is in an uplink symbol, and the random access opportunity is not overlapped with the first resource and the second resource in the time domain; or, the random access opportunity is not before the SSB in the PRACH slot and the random access opportunity start point is after at least Ngap symbols of the last downlink symbol, or after at least Ngap symbols of the last SSB received symbols, and the random access opportunity is not overlapped with both the first resource and the second resource in the time domain, then the random access opportunity is valid.

If the time division duplex uplink and downlink configuration is provided for the IAB node MT, if the random access opportunity is in an uplink symbol, and the random access opportunity is not overlapped with the first resource and the second resource in the time domain; or the random access opportunity is not in front of the SSB in the PRACH time slot and the starting point of the random access opportunity is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is not overlapped with the first resource and the second resource in the time domain; or the random access opportunity is not in front of the SSB in the PRACH time slot, the starting point of the random access opportunity is behind at least Ngap symbols of the last SSB received symbols, and the random access opportunity is not overlapped with the first resource and the second resource in the time domain; or, the random access opportunity is not before the SSB in the PRACH slot, and the start point of the random access is after at least Ngap symbols of the last SSB received symbol, and the start point of the random access is after at least Ngap symbols of the last downlink symbol, and the random access opportunity is not overlapped with both the first resource and the second resource in the time domain, then the random access opportunity is valid.

The first resource is an unavailable resource of the IAB node MT, and is provided by the unavailable resource configuration provided by parent IAB nodes for the IAB nodes.

The second resource is a hard resource of the IAB node DU, or a hard resource of the IAB node DU for transmission of an important signal or channel, or a hard UL resource of the IAB node DU for transmission of an important signal or channel.

In an alternative embodiment, the validity of the random access occasion may be determined according to existing mechanisms, and whether the valid random access occasion is available may be determined based on the unavailable resource:

and judging whether each random access opportunity is effective or not based on the existing rule for judging the effectiveness of the random access opportunity, wherein for each effective random access opportunity, if the effective random access opportunity is not overlapped with unavailable resources in a time domain, the effective random access opportunity is available, otherwise, the effective random access opportunity is unavailable.

And the unavailable resource is the resource indicated by the unavailable resource configuration.

In an optional embodiment, the validity of the random access occasion may also be judged according to an existing mechanism, and whether the valid random access occasion is available is determined based on available resources:

and judging whether each random access opportunity is effective or not based on the existing rule for judging the effectiveness of the random access opportunity, wherein for each effective random access opportunity, if the effective random access opportunity is in available resources, the effective random access opportunity is available, otherwise, the effective random access opportunity is unavailable.

In an optional embodiment, the validity of the random access time may also be determined according to an existing mechanism, and whether the random access time determined to be valid overlaps with the unavailable resource in the time domain is further determined. If there is no overlap, the random access occasion is valid.

The unavailable resource is a resource indicated by the unavailable resource configuration; or the first resource and/or the second resource in the above embodiments.

In an optional embodiment, the validity of the random access time may be further determined according to an existing mechanism, and whether the random access time determined to be valid is within the available resources is further determined. If within the available resources, the random access occasion is valid, otherwise it is invalid.

The available random access occasions or the available random access occasions may be used for transmitting the random access signal.

In an alternative embodiment, for the problem that the random access format spans a radio frame after offsetting the Subframe or slot in the configuration table, s _ offset may be applied to the entire configuration table, and according to the existing protocol, the duration of each random access format is shown in table 2, where OS is an OFDM symbol (OFDM symbol), and the duration thereof exceeds 1ms for

formats

1 and 2, since Subframe number is only the starting Subframe of PRACH opportunity, if s _ offset should reach the entire configuration table, then the case of preamble spanning a radio frame (frame) may occur.

For example, FR1TDD PRACH configuration index 30 occupies 3 subframes 7,8,9 in the time domain per RACH Occase (RO), and if s _ offset is 1, then each RO after the offset occupies subframe 8,9 in the time domain and subframe 0 of the next radio frame. Index 36 has similar problems.

FR1TDD PRACH configuration of Rel-15, PRACH resource start subframe of format 1 has only one value of 7, so for s _ offset of 1,2, the RO after offset spans the frame;

the PRACH resource start subframe of format 2 has only one value of 6, so for s _ offset 1,2,3, the RO after offset spans the frame.

Problems caused by RO across frames:

when the UL/DL configuration of the NR system needs to be aligned with the LTE TDD UL/DL configuration, subframe 0 of NR TDD should be a DL subframe, so the RO is invalid, possibly resulting in no available RACH resources;

the RO across frames may affect the orthogonality of the PRACH resources of the parent back haul link and the child link in the time domain, that is, if the RO across frames, the RACH resources of the parent back haul link and the child link of different frames may overlap in the time domain.

The problem of RO across frames can be solved using any of the following methods:

1. define rules for the IAB node whether ROs is valid, e.g., RO across frames is invalid;

2. when the ROs of the format 1 and the format 2 span the frame after the migration, the slot granularity is needed to judge the orthogonality of the parentbackhaul link and the PRACH resources of the child link in the time domain, because even the PRACH resources of different frames may not be orthogonal;

3. defining a rule: if the ROs corresponding to format 1/2 crosses the frame after the offset, then s _ offset is invalid for subframe number of format 1/format 2, i.e. s _ offset is considered to be 0, otherwise s _ offset is valid.

4. Subframe-based s _ offsets are configured separately for format 1 and format 2, and appropriate s _ offsets are configured.

5. Each index is individually configured with s _ offset, with the appropriate s _ offset.

Table 2: duration of the random access format:

Format	L_RA	Δf^RA	duration
				0	839	1.25kHz	1ms
1	839	1.25kHz	3ms
				2	839	1.25kHz	3.5ms
3	839	5kHz	1ms
				A1	139	15·2^μkHz	2OSs
A2	139	15·2^μkHz	4OSs
				A3	139	15·2^μkHz	6OSs
B1	139	15·2^μkHz	2OSs
				B2	139	15·2^μkHz	4OSs
B3	139	15·2^μkHz	6OSs
				B4	139	15·2^μkHz	12OSs
C0	139	15·2^μkHz	2OSs
				C2	139	15·2^μkHz	6OSs

in the above embodiments, the PRACH resources of the IAB node may be transmitted using system information common to the IAB nodes, e.g. IAB-SIB1, and the protocol predefines IAB node-specific IAB-SI-RNTI for scrambling the CRC of the scheduling system information PDCCH.

In the above embodiments, the IAB node is sometimes referred to as an IAB terminal (IAB node MT) for communicating with a parent node; sometimes referred to as an IAB base station (IAB node DU) for communicating with the child nodes. The IAB node specifically refers to which can be distinguished according to context.

The value of the Ngap is the same as that in the judgment of the effectiveness of the random access time slot of the common terminal.

IAB node MT and IAB node DU appearing in the same embodiment or the same example are two units of the same IAB node.

The random access opportunity overlapping with the SSB or the downlink symbol in the time domain is also invalid, that is, the judgment of the validity of the random access opportunity further needs to satisfy that the random access opportunity does not overlap with the SSB or the downlink symbol in the time domain.

It should be noted that in all the above embodiments and examples, the mapping relationship between the SSBs and the valid random access occasions is determined according to the existing mechanism.

In summary, the effectiveness of the random access timing is determined based on the unavailable resource configuration and the resource configuration of the IAB node DU, so that the effectiveness of the random access timing can be more reasonably determined, and unnecessary signal transmission is reduced to avoid unnecessary interference and power consumption. And a method for distinguishing random access responses of common UEs and IAB nodes is also provided, so that the problem that only one PRACH resource used by the UE and the IAB node can be successfully accessed randomly even if the PRACH resources used by the UE and the IAB node are different due to multiplexing of the random access responses of the UEs and the IAB nodes is solved.

In this embodiment, a method for transmitting a random access signal is provided, and fig. 6 is a flowchart of a method for transmitting a random access signal according to an embodiment of the present invention, as shown in fig. 6, the flowchart includes the following steps:

step S602, the second node receives the resource configuration information sent by the first node;

step S604, the second node determines the effectiveness of the random access opportunity based on the resource configuration information;

step S606, the second node sends a random access signal to the first node at an effective random access time.

Through the steps, the second node receives the resource configuration information sent by the first node, determines the effectiveness of the random access time based on the resource configuration information, sends the random access signal to the first node under the effective random access time, so that the purpose that the first node and the second node judge the effectiveness of the random access time based on the resource configuration information is achieved, the second node sends the random access signal within the effective random access time, and the first node receives the random access signal within the effective random access time. Therefore, the problem of effectiveness judgment of the random access time existing in the related technology can be solved, the effectiveness of the random access time can be judged more reasonably, and the effect of reducing useless signal transmission so as to avoid unnecessary interference and power consumption is achieved.

Optionally, the executing subject of the above steps may be a second node (e.g., IAB node), etc., but is not limited thereto.

The first node in this embodiment may be a Donor IAB DU or a parent IAB node DU. The second node may be an IAB node.

In this embodiment, the IAB node may be regarded as an ordinary terminal (UE) or a base station accessed by other UEs, fig. 3 is a schematic diagram of an architecture of an IAB network, and as shown in fig. 3, a node having a wired connection with a core network is called a donor IAB (donor IAB), and one donor IAB is wirelessly connected to one or more IAB nodes (IAB nodes) and provides a radio access function for UEs. There is no direct link between the IAB node and the core network, and its interaction with the core network requires one or more forwarding, and is finally realized by means of the donor IAB. The IAB node has two functions: 1) a Distributed Unit (DU) function, that is, an IAB node provides a radio access function for the UE or a sub-IAB node like a base station; 2) Mobile-Termination (MT) functionality, i.e. the IAB nodes are controlled and scheduled by the donor IAB or upper IAB nodes like the UE.

The Link between the Donor IAB and the IAB nodes and the Link between the IAB nodes are generally called Backhaul Link (BL), and the Link between the IAB node and the UE is called Access Link (AL). Considering that the IAB network supports multi-hop (for example, for the subordinate node of IAB node3, the connection to the donor IAB can be made through 4 hops, and the interaction with the core network is completed through the donor IAB), for more clear description of the link, specifically, for a specific IAB node, the link between the IAB node and its parent node, i.e., parent IAB node (which may be a normal IAB node or a donor IAB), is referred to as parent backhaul link (parent BL), the link between the IAB node and its child node (child IAB node) is referred to as child backhaul link (child BL), and the link between the IAB node and the UE is referred to as child access link (child AL). In order to ensure the robustness of the parent backhaul link, the IAB network supports redundant connections, for example, one IAB node may have one or more potential parent nodes in addition to the current parent node, as shown in fig. 3, and there is a wireless connection between IAB node4 and the donor IAB node, and also a potential wireless connection with IAB node 1.

In this embodiment, it can be applied to transmission of random signals between IAB nodes. In the half-duplex operation mode, the IAB nodes cannot simultaneously transmit and receive, for example, when the IAB node 2MT transmits a Random Access Preamble to the IAB node1, the IAB node cannot simultaneously receive the Random Access Preamble transmitted by the child IAB node3 or the child UEs, and the deployment location, antenna configuration, and mobility of the IAB node are greatly different from those of the general UE.

Further, in NR Release15, the configuration of random access resources is achieved by providing a random access occasion (PRACH opportunity, abbreviated as RO) of a start frequency and frequency domain multiplexing. The random access resource configuration is given in the form of table, different frequency band ranges and duplex modes correspond to different tables, each table contains 256 configurations, and the configuration indexes are 0 to 255. In actual configuration, the base station provides a configuration index. For example, in a frequency band TDD system (i.e. FR2and proposed spectrum) above 6GHz, the random access time domain resource configuration is shown in table 1 (only a part of the configuration is shown here due to the large number of rows in the table).

Table 1:

wherein the columns of table 1 have the following meanings:

column 1 PRACH config.index: configuring an index;

column 2 Preamble format: a random access format;

In an optional embodiment, considering that the IAB node needs to satisfy a half-duplex constraint (half-duplex constraint), that is, cannot simultaneously transmit and receive, the resource configuration information of the IAB node may include at least one of the following: the configuration index of a Physical Random Access Channel (PRACH), the frequency domain resource of the PRACH, the mapping relation between a Synchronization Signal Block (SSB) and random access opportunities (ROs) of RACH occasions, the initial logic root sequence index and cyclic shift (Ncs), the configuration period scaling factor (S) of the PRACH, the offset y _ offset based on a wireless frame, a time slot number, a subframe number and the configuration of unavailable resources.

The expanded PRACH configuration period is used as the PRACH configuration period of the IAB nodes, and the deviated radio frame or subframe or time slot is used as the subframe or time slot of the IAB nodes, wherein the subframe or the time slot contains the ROs; or the extended PRACH configuration period is used as the PRACH configuration period of the IABnodes, and the Parent IAB node may directly configure a slot number or a subframe number for replacing the slot number or the subframe number indicated by the PRACH configuration index. The replaced slotnumber or subframe number is the slot number or subframe number containing the ROs.

mode 1: and predefining multiple groups of configurations, wherein each group of configurations corresponds to a time slot index set or a subframe index set, each group of configurations is provided with a suoin index, and the configuration indexes are provided for the IAB node MT.

Mode 2: indicated by bitmap. For example, the slot number or subframe number corresponding to the bit value 1 is used to replace the slot number or subframe number indicated by the PRACH configuration index. duiyu

Since PRACH resources configurations of UEs and IAB nodes are different, UEs may not know PRACH resources of IAB nodes, and therefore, if Random Access Responses (RARs) of UEs and IAB nodes are multiplexed, a case may occur where only one of UEs and IAB nodes can successfully perform Random Access even though PRACH resources used by UEs and IAB nodes are different. For example, the UE and the IAB node MT use the same PRACH time-frequency resources, but the random access format and the preamble sequence are different (but the sequence indices both range from 0 to 64). That is, the IAB node generates the initial root sequence index of the preamble sequence, and the cyclic shift is different from that of the normal terminal, and it is expected that the normal terminal and the IAB terminal (IAB node MT) can be successfully accessed at the same time even if the same PRACH time-frequency resource and preamble sequence identifier are used. However, the existing mechanism enables the UE and the IAB node to correspond to the same RAR, and at most, only one random access can be successful. For another example, the PRACH resources of the UE and the IAB node have the same time domain starting position, but are orthogonal in the frequency domain (i.e. FDM), since the resource indexes of the UE and the IAB node in the frequency domain are both started from 0, for example, 8 common terminals are multiplexed in the frequency domain, 4 IAB nodes are multiplexed, and the frequency domain resource indexes corresponding to the two are 0 to 7 and 0 to 4, respectively. Therefore, even though the RACH resources of the two terminals do not overlap, the calculated RA-RNTIs may be the same, and if the preamble sequence identifiers used by the two terminals are also the same, the two terminals will correspond to the same RAR, and at most one random access can be successful. This not only increases the random access delay of the normal terminal or the IAB terminal, but also causes unnecessary interference in the subsequent random access procedure. Therefore, RARs that distinguish UEs from IAB nodes are needed. For example, the IAB nodes adopt a different RA-RNTI calculation formula than UEs, or indicate the MAC RAR of the IAB terminal by using the reserved domain of the MAC RAR.

In an alternative embodiment, the offset y _ offset of the radio frame comprises: and the offset is relative to a preset parameter y in a preset resource configuration table of the PRACH, wherein the preset parameter y refers to a radio frame index containing PRACH opportunity in a PRACH configuration period, and the preset parameter y is used for indicating a radio frame number containing the PRACH opportunity in the PRACH configuration period.

SF _ number mod (SF _ number + SF _ offset,10), where 0 ≦ SF _ offset < 10;

s _ number mod (S _ number + S _ offset,40), where 0 ≦ S _ offset < 40;

In an optional embodiment, in addition to the above parameters, the IAB nodes may receive parent IAB node and provide at least one PRACH related parameter as follows: the method comprises the steps of obtaining the total number of available random access lead codes, the total number of contention-based lead codes corresponding to each SSB, the total number of contention-based lead codes in a group A corresponding to each SSB, a threshold of the size of a transmission block of a selected preamble group, a path loss calculation parameter of the selected preamble group, a subcarrier interval used by a random access signal (msg1), an SSB received power threshold which needs to be met by the selected SSB and a corresponding PRACH resource, a power related parameter, a constraint set configuration, precoding of msg3 and the like.

In the above embodiment, it is assumed that the PRACH configuration period of the IAB nodes is a maximum of Tmax system frames. Alternatively, Tmax is one of 16,32,64,128, 256. The scaling factor S is 2k, where k is a non-negative integer whose maximum value depends on the maximum value of the PRACH configuration period of the IAB nodes.

wherein y is a parameter y in the PRACH configuration table.

Alternatively, Nprach is 8, then the two

equations

1 and 2 are:

RA-RNTI＝1+s_id+14×t_id+14×80×f_id+14×80×16×ul_carrier_id。

RA-RNTI＝1+s_id+14×t_id+14×80×(f_id+8)+14×80×16×ul_carrier_id

RA-RNTI＝1+s_id+14×t_id+14×160×f_id+14×160×8×ul_carrier_id

RA-RNTI＝1+s_id+14×(t_id+80)+14×160×f_id+14×160×8×ul_carrier_id

RA-RNTI＝1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id+14×80×8×2

RA-RNTI＝1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id

RA-RNTI＝1+s_id+s×t_id+s×t×f_id+s×t×f×ul_carrier_id；

-BI only: MAC subheader with Backoff indication only;

RAPID and RAR: MAC subheader with RAPID and MAC RAR.

As shown in fig. 5, a reserved bit R in a MAC RAR may be used to indicate whether the MAC RAR is a MAC RAR of IAB nodes. For example, R ═ 0 indicates a MAC RAR that is not an IAB nodes, and R ═ 1 indicates a MAC RAR that is an IAB nodes.

random access formats

under the condition that the first node does not provide uplink and downlink configuration of time division duplex for the second node, the random access time is effective under the condition that the random access time meets the following zhish: the random access opportunity is not in front of the SSB in the time slot of the PRACH, the starting point of the random access opportunity is after at least Ngap symbols of the last SSB receiving symbols, and the random access opportunity is not overlapped with the specific resource in the time domain;

wherein the specific resource comprises at least one of: resources that the second node cannot use, hard resources of a base station unit of the second node, hard resources that the base station unit of the second node uses to transmit important signals or channels, hard UL resources of the base station unit of the second node, and hard UL resources that the base station unit of the second node uses to transmit important signals or channels;

Optionally, the unavailable resource is at least one of: the method comprises the steps of determining unavailable resources of Parent IAB node DU, subset of the unavailable resources of Parent IAB node DU, the unavailable resources of potential Parent IAB node DU, subset of the unavailable resources of potential Parent IAB node DU, hard resource of child IAB node DU of Parent IAB node, hard UL resource of the child IAB node DU of Parent IAB node, unusable PRACH resource, and determining the unavailable resources according to the realization of the Parent IAB node DU.

if (L-1) < floor (N/2),

then RIV ═ N (L-1) + Tstart,

otherwise, RIV ═ N (N-L +1) + (N-1-Tstart)

Wherein k1, k2, M1, M2 and M3 are integers less than or equal to N.

If the time division duplex uplink and downlink configuration is provided for the IAB node MT, if the random access opportunity is in an uplink symbol, and the random access opportunity is not overlapped with the first resource in the time domain; or, the random access opportunity is not before the SSB in the PRACH slot and the random access opportunity start point is after at least Ngap symbols of the last downlink symbol, or after at least Ngap symbols of the last SSB received symbols, and the random access opportunity is not overlapped with the first resource in the time domain, the random access opportunity is valid.

Wherein the first resource is an IAB node MT unavailable resource. The IAB node MT may be obtained from the configuration of unavailable resources provided by parent IABnode for IAB nodes.

If the time division duplex uplink and downlink configuration is provided for the IAB node MT, if the random access opportunity is in an uplink symbol, and the random access opportunity is not overlapped with the second resource in the time domain; or, the random access opportunity is not before the SSB in the PRACH slot and the random access opportunity start point is after at least Ngap symbols of the last downlink symbol, or after at least Ngap symbols of the last SSB received symbols, and the random access opportunity is not overlapped with the second resource in the time domain, the random access opportunity is valid.

formats

Problems caused by RO across frames:

Table 2: duration of the random access format:

Through the above description of the embodiments, those skilled in the art can clearly understand that the method according to the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but the former is a better implementation mode in many cases. Based on such understanding, the technical solutions of the present invention may be embodied in the form of a software product, which is stored in a storage medium (e.g., ROM/RAM, magnetic disk, optical disk) and includes instructions for enabling a terminal device (e.g., a mobile phone, a computer, a server, or a network device) to execute the method according to the embodiments of the present invention.

In this embodiment, a receiving apparatus for a random access signal is further provided, and the apparatus is used to implement the foregoing embodiments and preferred embodiments, and details are not repeated for what has been described. As used below, the term "module" may be a combination of software and/or hardware that implements a predetermined function. Although the means described in the embodiments below are preferably implemented in software, an implementation in hardware, or a combination of software and hardware is also possible and contemplated.

Fig. 7 is a block diagram of a receiving apparatus of a random access signal according to an embodiment of the present invention, as shown in fig. 7, the apparatus including: a first sending module 72 and a first receiving module 74, which are described in detail below:

a first sending module 72, configured to send resource configuration information to the second node;

a first receiving module 74, connected to the first sending module 72, configured to receive a random access signal sent by the second node according to resource configuration information, where the resource configuration information is used to instruct the second node to send the random access signal at a valid random access time.

Through the module, the first node sends the resource configuration information to the second node, and receives the random access signal sent by the second node according to the resource configuration information, so that the purpose that the first node and the second node judge the effectiveness of the random access time based on the resource configuration information is achieved, the second node sends the random access signal in the effective random access time, and the first node receives the random access signal in the effective random access time. Therefore, the problem of effectiveness judgment of the random access time existing in the related technology can be solved, the effectiveness of the random access time can be judged more reasonably, and the effect of reducing useless signal transmission so as to avoid unnecessary interference and power consumption is achieved.

In an alternative embodiment, the resource configuration information includes at least one of: the method comprises the steps of configuring an index of a Physical Random Access Channel (PRACH), frequency domain resources of the PRACH, mapping relation between a Synchronous Signal Block (SSB) and random access occasions (ROs), initial logic root sequence index and cyclic shift (Ncs), configuration period scaling factors (S) of the PRACH, offset y _ offset based on a wireless frame, a time slot number, a subframe number, unavailable resource configuration and available resource configuration.

In an optional embodiment, the frequency domain resources of the PRACH include: a starting frequency of resources of the PRACH; the number of PRACH multiplexed in the frequency domain.

In an alternative embodiment, the starting frequency of the resources of the PRACH is determined by one of the following: the first node determines the starting frequency of the resources of the PRACH based on the activated upstream bandwidth BWP; the method comprises the steps that a first node determines the starting frequency of PRACH resources based on the offset of a starting physical resource block PRB of the PRACH frequency domain resources initially accessed by terminal equipment; the first node determines the starting frequency of the resources of the PRACH based on the offset of the terminating PRB of the initial access PRACH frequency domain resources of the terminal equipment.

In an alternative embodiment, the offset y _ offset of the radio frame comprises: and offset of a preset parameter y in a preset resource configuration table relative to the PRACH, wherein the preset parameter y refers to a radio frame index containing PRACH opportunity in a PRACH configuration period.

In an alternative embodiment, the radio frame number SFN at which the random access occasion is located satisfies one of the following formulas: mod (SFN, min { x S, Tmax }) ═ mod (y + y _ offset, min { x S, Tmax }), where y _ offset is an integer and 0 ≦ y _ offset < Tmax; mod (SFN, x S) ═ y _ offset, where y _ offset is an integer and 0 ≦ y _ offset < x S; wherein, x and y are parameters in a preset resource configuration table of the PRACH, and Tmax is a maximum value of a configuration period of the PRACH allowed by the second node.

In an optional embodiment, after a first node receives a random access signal sent by a second node according to resource configuration information, the first node sends a random access response to the second node, wherein a Cyclic Redundancy Check (CRC) of a Physical Downlink Control Channel (PDCCH) corresponding to the random access response is scrambled by using an RA-RNTI; the RA-RNTI corresponds to a PRACH for transmitting random access signals, and the calculation formula of the RA-RNTI comprises the following steps: RA-RNTI + 1+ s _ id +14 × t _ id +14 × 80 × f _ id +14 × 80 × 8 × ul _ carrier _ id +14 × 80 × 8 × 2; s _ id is the symbol index of the first orthogonal frequency division multiplexing OFDM of the PRACH, and s _ id is more than or equal to 0 and less than 14; t _ id is the first time slot index of PRACH, t _ id is more than or equal to 0 and less than 80; f _ id is the frequency domain index of PRACH, and f _ id is more than or equal to 0 and less than 8; ul _ carrier _ id is an uplink carrier for indicating PRACH transmission of a random access signal.

In an optional embodiment, after the first node receives a random access signal sent by the second node according to the resource configuration information, the first node sends a random access response to the second node, where a reserved domain of a MAC-RAR in the random access response indicates that the MAC-RAR is a MAC-RAR of the second node.

In an optional embodiment, each MAC-RAR corresponds to a sub-header, and the sub-header includes a random access preamble identifier RAPID; the subheader and the MAC-RAR form a media access control protocol data unit MAC subpPDU; and under the condition that the RAPID corresponding to the random access signal sent by the terminal equipment in the protocol data unit MAC-PDU of the media access control is the same as the RAPID corresponding to the random access signal sent by the second node, the MAC sub PDU of the terminal equipment is in front of the MAC sub PDU of the second node.

In an alternative embodiment, the subframe number comprises: and the subframe number indicated by the PRACH configuration index in the preset resource configuration table for replacing the PRACH, wherein the replaced subframe number is an index set comprising the ROs subframes.

In an alternative embodiment, the slot number comprises: and the time slot number is used for replacing the time slot number indicated by the PRACH configuration index in the preset resource configuration table of the PRACH, wherein the replaced time slot number is an index set comprising the ROs time slot.

In an optional embodiment, before the first node receives the random access signal sent by the second node according to the resource configuration information, the method further includes: the first node judges the effectiveness of the random access opportunity, wherein the judgment of the effectiveness of the random access opportunity by the first node comprises one of the following steps: in the case where the first node does not provide uplink and downlink configuration for time division duplexing to the second node, the random access occasion is valid if the random access occasion satisfies the following condition: the random access occasion is not in front of the SSB in the time slot of the PRACH, the starting point of the random access occasion is after at least Ngap symbols of the last SSB received symbols, and the random access occasion is not overlapped with the specific resource in the time domain; under the condition that the first node provides uplink and downlink configuration of time division duplex for the second node, the random access time is effective under the condition that the random access time meets one of the following conditions: the random access opportunity is in the uplink symbol, and the random access opportunity is not overlapped with the specific resource in the time domain; the random access opportunity is not in front of SSB in the PRACH time slot, the starting point of the random access is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is not overlapped with specific resources on the time domain; the random access opportunity is not in front of SSB in the PRACH time slot, the starting point of the random access is behind at least Ngap symbols of the last SSB receiving symbols, and the random access opportunity is not overlapped with specific resources on the time domain; the random access opportunity is not in front of the SSB in the PRACH time slot, the starting point of the random access is behind at least Ngap symbols of the last SSB receiving symbols, the starting point of the random access is behind at least Ngap symbols of the last downlink symbols, and the random access opportunity is not overlapped with the specific resource in the time domain; wherein the specific resource comprises at least one of: resources that the second node cannot use, hard resources of a base station unit of the second node, hard resources that the base station unit of the second node uses to transmit important signals or channels, hard UL resources of the base station unit of the second node, and hard UL resources that the base station unit of the second node uses to transmit important signals or channels; the important signals or channels include at least one of: SSB, system information, PRACH, signal or channel of URLLC.

In an optional embodiment, before the first node receives the random access signal sent by the second node according to the resource configuration information, the method further includes: the first node judges the effectiveness of the random access opportunity, wherein the judgment of the effectiveness of the random access opportunity by the first node comprises one of the following steps:

under the condition that the first node does not provide uplink and downlink configuration of time division duplex for the second node and the random access time in the PRACH time slot meets the following conditions, the random access time is effective: the random access opportunity is not in front of the SSB in the PRACH time slot, the random access opportunity is in a specific resource after the starting point of the random access opportunity is at least Ngap symbols of the last SSB receiving symbols;

when the first node provides uplink and downlink configuration of time division duplex for the second node and the random access time in the PRACH time slot meets one of the following conditions, the random access time is effective: the random access time is in the uplink symbol and the random access time is in the specific resource; the random access opportunity is not in front of SSB in PRACH time slot, and the starting point of random access is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is in specific resources; the random access opportunity is not in front of the SSB in the PRACH time slot, and the starting point of the random access is behind at least Ngap symbols of the last SSB receiving symbols, and the random access opportunity is in a specific resource; the random access opportunity is not in front of the SSB in the PRACH time slot, the starting point of the random access is behind at least Ngap symbols of the last SSB receiving symbols, the starting point of the random access is behind at least Ngap symbols of the last downlink symbols, and the random access opportunity is in a specific resource;

wherein the specific resource comprises at least one of: the resources indicated by the available resource configuration, non-hard resources of the base station unit of the second node, non-hard UL resources of the base station unit of the second node, and unavailable resources of the base station unit of the second node.

Fig. 8 is a block diagram of a structure of a transmission apparatus of a random access signal according to an embodiment of the present invention, as shown in fig. 8, the apparatus including: a second receiving module 82, a determining module 84, and a second sending module 86, which are described in detail below:

a second receiving module 82, configured to receive resource configuration information sent by the first node;

a determining module 84, connected to the second receiving module 82, configured to determine validity of the random access occasion based on the resource configuration information;

the second sending module 86 is connected to the determining module 84, and configured to send the random access signal to the first node at the valid random access time.

Through the module, the second node receives the resource configuration information sent by the first node, determines the effectiveness of the random access time based on the resource configuration information, sends the random access signal to the first node under the effective random access time, so that the purpose that the first node and the second node judge the effectiveness of the random access time based on the resource configuration information is achieved, the second node sends the random access signal within the effective random access time, and the first node receives the random access signal within the effective random access time. Therefore, the problem of effectiveness judgment of the random access time existing in the related technology can be solved, the effectiveness of the random access time can be judged more reasonably, and the effect of reducing useless signal transmission so as to avoid unnecessary interference and power consumption is achieved.

In an alternative embodiment, the starting frequency of the resources of the PRACH is determined by one of the following information: an activated upstream bandwidth BWP; offset of a starting physical resource block PRB of an initial access PRACH frequency domain resource of the terminal equipment; offset of a terminating PRB of an initial access PRACH frequency domain resource of a terminal device.

In an optional embodiment, after the second node sends a random access signal to the first node at an effective random access time, the second node receives a random access response sent by the first node, and descrambles a Cyclic Redundancy Check (CRC) of a Physical Downlink Control Channel (PDCCH) corresponding to the random access response by using an RA-RNTI; the RA-RNTI corresponds to a PRACH for transmitting random access signals, and the calculation formula of the RA-RNTI comprises the following steps: RA-RNTI + 1+ s _ id +14 × t _ id +14 × 80 × f _ id +14 × 80 × 8 × ul _ carrier _ id +14 × 80 × 8 × 2; s _ id is the symbol index of the first orthogonal frequency division multiplexing OFDM of the PRACH, and s _ id is more than or equal to 0 and less than 14; t _ id is the first time slot index of PRACH, t _ id is more than or equal to 0 and less than 80; f _ id is the frequency domain index of PRACH, and f _ id is more than or equal to 0 and less than 8; ul _ carrier _ id is an uplink carrier for indicating PRACH transmission of a random access signal.

In an optional embodiment, after the second node sends the random access signal to the first node at the valid random access occasion, the second node receives a random access response sent by the first node, and determines whether the MAC-RAR is the MAC-RAR of the second node according to a reserved domain of the MAC-RAR in the random access response.

In an optional embodiment, each MAC-RAR corresponds to a sub-header, and the sub-header includes a random access preamble identifier RAPID; the subheader and the MAC-RAR form a media access control subprotocol data unit MAC subPDU; and under the condition that the RAPID corresponding to the random access signal sent by the terminal equipment in the protocol data unit MAC-PDU of the media access control is the same as the RAPID corresponding to the random access signal sent by the second node, the MAC sub PDU of the terminal equipment is in front of the MAC sub PDU of the second node.

In an optional embodiment, the random access occasion is valid when the first node does not provide uplink and downlink configuration of time division duplex for the second node, and the random access occasion in the PRACH time slot satisfies the following conditions: the random access opportunity is not in front of the SSB in the time slot of the PRACH, the starting point of the random access opportunity is after at least Ngap symbols of the last SSB receiving symbols, and the random access opportunity is not overlapped with the specific resource in the time domain;

when the first node provides uplink and downlink configuration of time division duplex for the second node and the random access time in the PRACH time slot meets one of the following conditions, the random access time is effective: the random access opportunity is in the uplink symbol, and the random access opportunity is not overlapped with the specific resource in the time domain; the random access opportunity is not in front of SSB in PRACH time slot, and the starting point of random access is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is not overlapped with specific resources on time domain; the random access opportunity is not in front of SSB in the PRACH time slot, the starting point of the random access is behind at least Ngap symbols of the last SSB receiving symbols, and the random access opportunity is not overlapped with specific resources on the time domain; the random access opportunity is not in front of the SSB in the PRACH time slot, the starting point of the random access is behind at least Ngap symbols of the last SSB receiving symbols, the starting point of the random access is behind at least Ngap symbols of the last downlink symbols, and the random access opportunity is not overlapped with the specific resources in the time domain;

wherein the specific resource comprises at least one of: the resource indicated by the unavailable resource configuration, the hard resource of the base station unit of the second node, the hard resource used by the base station unit of the second node for transmitting the important signal or channel, the hard UL resource of the base station unit of the second node, and the hard UL resource used by the base station unit of the second node for transmitting the important signal or channel;

In an optional embodiment, before the second node sends the random access signal to the first node in the valid random access occasion, the method further includes: the second node judges the effectiveness of the random access time, wherein the judgment of the effectiveness of the random access time by the second node comprises one of the following steps:

wherein the specific resource comprises at least one of: resources indicated by the available resource configuration, non-hard resources of the base station unit of the second node, non-hard UL resources of the base station unit of the second node, and unavailable resources of the base station unit of the second node;

it should be noted that, the above modules may be implemented by software or hardware, and for the latter, the following may be implemented, but not limited to: the modules are all positioned in the same processor; alternatively, the modules are respectively located in different processors in any combination.

Embodiments of the present invention also provide a storage medium having a computer program stored therein, wherein the computer program is arranged to perform the steps of any of the above method embodiments when executed.

Alternatively, in the present embodiment, the storage medium may be configured to store a computer program for executing the above steps.

Optionally, in this embodiment, the storage medium may include, but is not limited to: various media capable of storing computer programs, such as a usb disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a removable hard disk, a magnetic disk, or an optical disk.

Embodiments of the present invention also provide an electronic device comprising a memory having a computer program stored therein and a processor arranged to run the computer program to perform the steps of any of the above method embodiments.

Optionally, the electronic apparatus may further include a transmission device and an input/output device, wherein the transmission device is connected to the processor, and the input/output device is connected to the processor.

Alternatively, in this embodiment, the processor may be configured to execute the above steps through a computer program.

Optionally, the specific examples in this embodiment may refer to the examples described in the above embodiments and optional implementation manners, and this embodiment is not described herein again.

It will be apparent to those skilled in the art that the modules or steps of the present invention described above may be implemented by a general purpose computing device, they may be centralized on a single computing device or distributed across a network of multiple computing devices, and alternatively, they may be implemented by program code executable by a computing device, such that they may be stored in a storage device and executed by a computing device, and in some cases, the steps shown or described may be performed in an order different than that described herein, or they may be separately fabricated into individual integrated circuit modules, or multiple ones of them may be fabricated into a single integrated circuit module. Thus, the present invention is not limited to any specific combination of hardware and software.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for receiving a random access signal, comprising:

a first node sends resource configuration information to a second node;

and the first node receives a random access signal sent by the second node according to the resource configuration information, wherein the resource configuration information is used for indicating the second node to send the random access signal at an effective random access opportunity.

2. The method of claim 1, wherein the resource configuration information comprises at least one of:

the configuration method comprises the steps of configuration index of a Physical Random Access Channel (PRACH), frequency domain resource of the PRACH, mapping relation between a Synchronous Signal Block (SSB) and random access time (ROs), initial logic root sequence index and cyclic shift (Ncs), configuration period scaling factor S of the PRACH, offset y _ offset based on a wireless frame, time slot number, subframe number, unavailable resource configuration and available resource configuration.

3. The method of claim 2, wherein the frequency domain resources of the PRACH comprise:

a starting frequency of resources of the PRACH;

the number of PRACHs multiplexed in the frequency domain.

4. The method of claim 3, wherein a starting frequency of the resources of the PRACH is determined by one of:

the first node determines a starting frequency of resources of the PRACH based on the activated upstream bandwidth BWP;

the first node determines the starting frequency of the PRACH resource based on the offset of the starting Physical Resource Block (PRB) of the PRACH frequency domain resource initially accessed by the terminal equipment;

the first node determines the starting frequency of the PRACH resource based on the offset of the termination PRB of the initial access PRACH frequency domain resource of the terminal equipment.

5. The method of claim 2, wherein the offset y _ offset of the radio frame comprises:

and the offset is relative to a preset parameter y in a preset resource configuration table of the PRACH, wherein the preset parameter y refers to a radio frame index containing PRACH opportunity in a PRACH configuration period.

6. The method of claim 5, wherein the radio frame number SFN at which the random access occasion is located satisfies one of the following formulas:

mod (SFN, min { x S, Tmax }) ═ mod (y + y _ offset, min { x S, Tmax }), where y _ offset is an integer and 0 ≦ y _ offset < Tmax;

mod (SFN, x S) ═ y _ offset, where y _ offset is an integer and 0 ≦ y _ offset < x S;

wherein x and y are parameters in a preset resource configuration table of the PRACH, and Tmax is a maximum value of a configuration period of the PRACH allowed by the second node.

7. The method of claim 1, wherein after the first node receives the random access signal sent by the second node according to the resource configuration information, the method further comprises:

the first node sends a random access response to the second node, wherein the Cyclic Redundancy Check (CRC) of a Physical Downlink Control Channel (PDCCH) corresponding to the random access response is scrambled by using a random access radio network temporary identifier (RA-RNTI);

the RA-RNTI corresponds to a PRACH for transmitting the random access signal, and a calculation formula of the RA-RNTI comprises the following steps:

RA-RNTI＝1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id+14×80×8×2；

the s _ id is a symbol index of the first orthogonal frequency division multiplexing OFDM of the PRACH, and s _ id is more than or equal to 0 and less than 14; the t _ id is the first time slot index of the PRACH, and t _ id is more than or equal to 0 and less than 80; the f _ id is the frequency domain index of the PRACH, and f _ id is more than or equal to 0 and less than 8; the ul _ carrier _ id is an uplink carrier for indicating the PRACH to transmit a random access signal.

8. The method of claim 1, wherein after the first node receives the random access signal sent by the second node according to the resource configuration information, the method further comprises:

the first node sends a random access response to the second node, wherein a reserved domain of a media access response MAC-RAR in the random access response indicates that the MAC-RAR is the MAC-RAR of the second node.

9. The method of claim 8,

each MAC-RAR corresponds to a sub-header, and the sub-header comprises a Random Access Preamble Identifier (RAPID);

the subheader and the MAC-RAR form a media access control subprotocol data unit (MAC subPDU);

and under the condition that the RAPID corresponding to the random access signal sent by the terminal equipment in the protocol data unit MAC-PDU controlled by the media access is the same as the RAPID corresponding to the random access signal sent by the second node, the MAC sub PDU of the terminal equipment is in front of the MAC sub PDU of the second node.

10. The method of claim 2, wherein the subframe number comprises:

and the subframe number is used for replacing the subframe number indicated by the PRACH configuration index in the preset resource configuration table of the PRACH, wherein the replaced subframe number is an index set comprising the ROs subframe.

11. The method of claim 2, wherein the slot number comprises:

and the time slot number is used for replacing the time slot number indicated by the PRACH configuration index in the preset resource configuration table of the PRACH, wherein the replaced time slot number is an index set comprising the ROs time slot.

12. The method according to claim 2, wherein before the first node receives the random access signal sent by the second node according to the resource configuration information, further comprising: the first node judges the effectiveness of the random access opportunity, wherein the judgment of the effectiveness of the random access opportunity by the first node comprises one of the following steps:

when the first node does not provide uplink and downlink configuration of time division duplex for the second node, and a random access opportunity in a PRACH time slot meets the following conditions, the random access opportunity is valid: the random access occasion is not ahead of an SSB within the PRACH slot, a starting point of the random access occasion is after at least Ngap symbols of a last SSB received symbol, and the random access occasion is not overlapped with a specific resource in a time domain;

when the first node provides uplink and downlink configuration of time division duplex for the second node and a random access opportunity in a PRACH time slot meets one of the following conditions, the random access opportunity is effective: the random access opportunity is in an uplink symbol, and the random access opportunity is not overlapped with a specific resource in a time domain; the random access opportunity is not in front of the SSB in the PRACH time slot, the starting point of random access is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is not overlapped with specific resources on the time domain; the random access occasion is not before an SSB within the PRACH slot, and a starting point of the random access is after at least Ngap symbols of a last SSB received symbol, and the random access occasion is not overlapped with a specific resource in a time domain; the random access occasion is not before an SSB within the PRACH slot, and a start point of the random access is after at least Ngap symbols of a last SSB received symbol, and the start point of the random access is after at least Ngap symbols of a last downlink symbol, and the random access occasion is not overlapped with a specific resource in a time domain;

wherein the specific resource comprises at least one of: the resource indicated by the unavailable resource configuration, the hard resource of the base station unit of the second node, the hard UL resource of the base station unit of the second node, and the hard UL resource of the base station unit of the second node, are used for transmitting the important signal or channel;

13. The method according to claim 2, wherein before the first node receives the random access signal sent by the second node according to the resource configuration information, further comprising: the first node judges the effectiveness of the random access opportunity, wherein the judgment of the effectiveness of the random access opportunity by the first node comprises one of the following steps:

when the first node does not provide uplink and downlink configuration of time division duplex for the second node, and a random access opportunity in a PRACH time slot satisfies the following conditions, the random access opportunity is valid: the random access occasion is not ahead of an SSB within a PRACH slot, the random access occasion starting after at least Ngap symbols of a last SSB received symbol, the random access occasion being within a particular resource;

when the first node provides uplink and downlink configuration of time division duplex for the second node and a random access opportunity in the PRACH time slot meets one of the following conditions, the random access opportunity is effective: the random access opportunity is in an uplink symbol, and the random access opportunity is in a specific resource; the random access opportunity is not in front of the SSB in the PRACH time slot, and the starting point of the random access is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is in a specific resource; the random access occasion is not before an SSB within the PRACH slot, and a start point of random access is after at least Ngap symbols of a last SSB received symbol, and the random access occasion is within a specific resource; the random access occasion is not before an SSB within the PRACH slot, and a start of the random access is after at least Ngap symbols of a last SSB received symbol, and a start of the random access is after at least Ngap symbols of a last downlink symbol, and the random access occasion is within a particular resource;

wherein the specific resource comprises at least one of: the resource indicated by the available resource configuration, the non-hard resource of the base station unit of the second node, the non-hard UL resource of the base station unit of the second node, and the unavailable resource of the base station unit of the second node.

14. A method for transmitting a random access signal, comprising:

the second node receives the resource configuration information sent by the first node;

the second node determines the validity of the random access opportunity based on the resource configuration information;

and the second node sends a random access signal to the first node at an effective random access opportunity.

15. The method of claim 14, wherein the resource configuration information comprises at least one of:

16. The method of claim 15, wherein the frequency domain resources of the PRACH comprise:

a starting frequency of resources of the PRACH;

the number of PRACHs multiplexed in the frequency domain.

17. The method of claim 16, wherein a starting frequency of the resources of the PRACH is determined by one of:

an activated upstream bandwidth BWP;

offset of a starting physical resource block PRB of an initial access PRACH frequency domain resource of the terminal equipment;

offset of a terminating PRB of an initial access PRACH frequency domain resource of a terminal device.

18. The method of claim 15, wherein the offset y _ offset of the radio frame comprises:

19. The method of claim 18, wherein a radio frame number (SFN) at which the random access occasion is located satisfies one of the following formulas:

20. The method of claim 14, wherein after the second node transmits a random access signal to the first node at a valid random access occasion, the method further comprises:

the second node receives a random access response sent by the first node, and descrambles the Cyclic Redundancy Check (CRC) of a Physical Downlink Control Channel (PDCCH) corresponding to the random access response by using an RA-RNTI (random access-radio network temporary identifier);

RA-RNTI＝1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id+14×80×8×2；

21. The method of claim 14, wherein after the second node transmits a random access signal to the first node at a valid random access occasion, the method further comprises:

and the second node receives the random access response sent by the first node, and determines whether the MAC-RAR is the MAC-RAR of the second node according to the reserved domain of the MAC-RAR in the random access response.

22. The method of claim 21,

23. The method of claim 15, wherein the subframe number comprises:

24. The method of claim 15, wherein the slot number comprises:

25. The method of claim 15, wherein before the second node sends a random access signal to the first node at a valid random access occasion, further comprising: the second node judges the effectiveness of the random access opportunity, wherein the judgment of the effectiveness of the random access opportunity by the second node comprises one of the following steps:

when the first node does not provide uplink and downlink configuration of time division duplex for the second node, and a random access opportunity in a PRACH time slot meets the following conditions, the random access opportunity is valid: the random access occasion is not ahead of an SSB within a time slot of the PRACH, a start point of the random access occasion is after at least Ngap symbols of a last SSB received symbol, and the random access occasion is not overlapped with a specific resource in a time domain;

when the first node provides uplink and downlink configuration of time division duplex for the second node and a random access opportunity in a PRACH time slot meets one of the following conditions, the random access opportunity is effective: the random access opportunity is in an uplink symbol, and the random access opportunity is not overlapped with a specific resource in a time domain; the random access opportunity is not in front of the SSB in the PRACH time slot, the starting point of the random access is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is not overlapped with a specific resource in the time domain; the random access occasion is not in front of the SSB in the PRACH time slot, the starting point of random access is behind at least Ngap symbols of the last SSB receiving symbols, and the random access occasion is not overlapped with specific resources in the time domain; the random access occasion is not before an SSB within the PRACH slot, and a start point of the random access is after at least Ngap symbols of a last SSB received symbol, and the start point of the random access is after at least Ngap symbols of a last downlink symbol, and the random access occasion is not overlapped with a specific resource in a time domain;

26. The method of claim 15, wherein before the second node sends a random access signal to the first node at a valid random access occasion, further comprising: the second node judges the effectiveness of the random access opportunity, wherein the judgment of the effectiveness of the random access opportunity by the second node comprises one of the following steps:

when the first node does not provide uplink and downlink configuration of time division duplex for the second node, and a random access opportunity in a PRACH time slot satisfies the following conditions, the random access opportunity is valid: the random access occasion is not before an SSB within the PRACH slot, the random access occasion starting at a point at least Ngap symbols after a last SSB received symbol, the random access occasion being within a particular resource;

when the first node provides uplink and downlink configuration of time division duplex for the second node and a random access opportunity in the PRACH time slot meets one of the following conditions, the random access opportunity is effective: the random access opportunity is in an uplink symbol, and the random access opportunity is in a specific resource; the random access opportunity is not in front of the SSB in the PRACH time slot, and the starting point of random access is behind at least Ngap symbols of the last downlink symbol, and the random access opportunity is in a specific resource; the random access occasion is not before an SSB within the PRACH slot, and the start of the random access is after at least Ngap symbols of the last SSB received symbols, and the random access occasion is within a specific resource; the random access occasion is not before an SSB within the PRACH slot, and a start of the random access is after at least Ngap symbols of a last SSB received symbol, and a start of the random access is after at least Ngap symbols of a last downlink symbol, and the random access occasion is within a particular resource;

27. An apparatus for receiving a random access signal, comprising:

a first sending module, configured to send resource configuration information to a second node;

a first receiving module, configured to receive a random access signal sent by the second node according to the resource configuration information, where the resource configuration information is used to instruct the second node to send the random access signal at an effective random access time.

28. A transmission apparatus for a random access signal, comprising:

a second receiving module, configured to receive resource configuration information sent by the first node;

a determining module, configured to determine validity of a random access occasion based on the resource configuration information;

and the second sending module is used for sending a random access signal to the first node at the effective random access time.

29. A storage medium having stored thereon a computer program, wherein the computer program is arranged to perform the method of any of claims 1 to 13 when executed or wherein the computer program is arranged to perform the method of any of claims 14 to 26 when executed.

30. An electronic apparatus comprising a memory and a processor, wherein the memory has stored therein a computer program, and wherein the processor is arranged to execute the computer program to perform the method of any of claims 1 to 13, or wherein the processor is arranged to execute the computer program to perform the method of any of claims 14 to 26.